JP2016213285A - Atomic cell, quantum interference device, atomic oscillator, electronic apparatus and moving object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an atomic cell capable of improving frequency stability, and to provide a quantum interference device, an atomic oscillator, an electronic apparatus and a moving object including the atomic cell.SOLUTION: An atomic cell 2 of the present invention includes: alkali metal atoms; a pair of light-transmitting parts 22, 23; a body part 21 constituting an inner space S storing the alkali metal atoms together with the pair of light-transmitting parts 22, 23; and a dissimilar material part 24 comprising a material having a thermal conductivity greater than that of the light-transmitting parts 22, 23. The inner space S has a metal reservoir storing an alkali metal M in a liquid or solid state; and the dissimilar material part 24 is disposed between the metal reservoir and an exterior of the inner space S.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an atomic cell, a quantum interference device, an atomic oscillator, an electronic device, and a moving object.

  As an oscillator having long-term highly accurate oscillation characteristics, an atomic oscillator that oscillates based on energy transition of an alkali metal atom such as rubidium or cesium is known.

  In general, the operating principles of atomic oscillators are broadly divided into methods that use the double resonance phenomenon of light and microwaves, and methods that use the quantum interference effect (CPT: Coherent Population Trapping) of two types of light with different wavelengths. Is done.

  In any type of atomic oscillator, an alkali metal is usually enclosed in a gas cell (atomic cell), and the gas cell is heated to a predetermined temperature by a heater in order to keep the alkali metal in a certain gas state.

  For example, as disclosed in Patent Document 1, generally, an excess alkali metal is enclosed in a gas cell in anticipation of an amount by which the alkali metal decreases with time. Such surplus alkali metal is present as a liquid by being deposited (condensation) in the low temperature portion of the gas cell.

  However, in the past, surplus alkali metal adheres to the excitation light passage region, and the amount of excitation light irradiated onto the alkali metal varies or decreases, resulting in a fluctuation in frequency. There was a problem that the stability decreased. In particular, with the recent demand for miniaturization of atomic oscillators and the like, when the atomic cell becomes smaller, the temperature difference between the excitation light transmission region and the other regions becomes smaller, and alkali metal is present in the excitation light passage region. Such a problem becomes conspicuous because it tends to adhere.

JP2013-38382A

  An object of the present invention is to provide an atomic cell that can improve the frequency stability, and to provide a quantum interference device, an atomic oscillator, an electronic apparatus, and a moving body including the atomic cell.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1]
The atomic cell of the present invention comprises a metal atom,
A pair of light transmission parts;
A body part that constitutes an internal space containing the metal atoms together with the pair of light transmission parts;
A dissimilar material part including a material having a higher thermal conductivity than the light transmission part;
With
The internal space has a metal reservoir that stores the metal atom in a liquid or solid state,
The dissimilar material part is arranged between the outside of the internal space and the metal reservoir part.

  According to such an atomic cell, since the thermal conductivity of the dissimilar material part is larger than that of the light transmitting part, the dissimilar material part is easier to dissipate heat than the light transmitting part. Therefore, the temperature of the dissimilar material part can be made lower than that of the light transmitting part, and as a result, it is possible to prevent or reduce liquid or solid metal atoms from condensing and adhering to the light transmitting part. Therefore, frequency stability can be improved.

[Application Example 2]
In the atomic cell of the present invention, the dissimilar material portion preferably faces the inside and outside of the internal space.

  Thereby, it can be made easy to radiate heat from the inside of the internal space to the outside via the dissimilar material part.

[Application Example 3]
In the atomic cell of the present invention, it is preferable that the dissimilar material part is disposed in the light transmission part.

  Thereby, when forming an atomic cell by bonding together a plurality of substrates for forming a pair of light transmission parts and a body part, formation of a different material part can be simplified.

[Application Example 4]
In the atomic cell of the present invention, the internal space has a gas storage portion that stores the gaseous metal atoms,
It is preferable that a wall portion is disposed between the gas storage portion and the metal reservoir portion.

  Thereby, it can reduce that a liquid or solid metal atom moves to a gas storage part from a metal reservoir part. As a result, the frequency stability can be further improved.

[Application Example 5]
In the atomic cell of the present invention, the light transmission part includes glass,
The dissimilar material part preferably contains silicon.

  Thereby, a light transmissive part and a dissimilar material part can be joined simply and firmly by anodic bonding. In addition, since the light-transmitting part and the dissimilar material part can be hermetically bonded, even when the dissimilar material part is used for sealing the sealing hole, the airtightness of the internal space is excellent. be able to.

[Application Example 6]
In the atomic cell of the present invention, it is preferable that the dissimilar material part is disposed in the body part.
Thereby, size reduction of an atomic cell can be achieved.

[Application Example 7]
In the atomic cell of the present invention, the dissimilar material part and its peripheral part are preferably directly joined.

  Thereby, a dissimilar material part and its peripheral part can be joined easily and firmly. In addition, since the dissimilar material part and its peripheral part can be hermetically bonded, even if the dissimilar material part is used for sealing the sealing hole, the airtightness of the internal space is excellent. be able to.

[Application Example 8]
The quantum interference device of the present invention includes the atomic cell of the present invention.
According to such a quantum interference device, the frequency stability can be made excellent.

[Application Example 9]
The atomic oscillator of the present invention includes the atomic cell of the present invention.
According to such an atomic oscillator, the frequency stability can be improved.

[Application Example 10]
The electronic device of the present invention includes the atomic cell of the present invention.

  According to such an electronic device, since the frequency stability of the atomic cell is excellent, excellent reliability can be exhibited.

[Application Example 11]
The moving body of the present invention includes the atomic cell of the present invention.

  According to such a moving body, since the frequency stability of the atomic cell is excellent, excellent reliability can be exhibited.

1 is a schematic diagram showing an atomic oscillator (quantum interference device) according to a first embodiment of the present invention. It is a figure for demonstrating the energy state of an alkali metal. It is a graph which shows the relationship between the frequency difference of two light radiate | emitted from a light-projection part, and the intensity | strength of the light detected by a photon detection part. It is a perspective view of the atomic cell with which the atomic oscillator shown in FIG. 1 is provided. (A) is a longitudinal cross-sectional view of the atomic cell shown in FIG. 4, and (b) is a cross-sectional view of the atomic cell shown in FIG. It is a graph which shows the relationship between the ratio of the thermal conductivity of a dissimilar material part with respect to the thermal conductivity of a light transmissive part, and frequency stability. It is a figure for demonstrating the manufacturing method of the atomic cell shown in FIG. It is a figure for demonstrating the manufacturing method of the atomic cell shown in FIG. (A) is a longitudinal cross-sectional view which shows the atomic cell which concerns on 2nd Embodiment of this invention, (b) is a cross-sectional view of the atomic cell shown to (a). It is a longitudinal cross-sectional view which shows the atomic cell which concerns on 3rd Embodiment of this invention. (A) is a longitudinal cross-sectional view which shows the atomic cell which concerns on 4th Embodiment of this invention, (b) is a cross-sectional view of the atomic cell shown to (a). It is a figure which shows schematic structure at the time of using the atomic oscillator of this invention for the positioning system using a GPS satellite. It is a figure which shows an example of the moving body of this invention.

  Hereinafter, an atomic cell, a quantum interference device, an atomic oscillator, an electronic device, and a moving body of the present invention will be described in detail based on embodiments shown in the accompanying drawings.

1. Atomic oscillator (quantum interference device)
First, the atomic oscillator of the present invention (the atomic oscillator including the atomic cell of the present invention) will be described. In the following, an example in which the quantum interference device of the present invention is applied to an atomic oscillator will be described. However, the quantum interference device of the present invention is not limited to this, for example, a magnetic sensor, a quantum memory, etc. It is also applicable to.

<First Embodiment>
FIG. 1 is a schematic diagram showing an atomic oscillator (quantum interference device) according to a first embodiment of the present invention. 2 is a diagram for explaining the energy state of the alkali metal, and FIG. 3 is a relationship between the frequency difference between the two lights emitted from the light emitting part and the intensity of the light detected by the light detecting part. It is a graph which shows.

  An atomic oscillator 1 shown in FIG. 1 is an atomic oscillator using a quantum interference effect. As shown in FIG. 1, the atomic oscillator 1 includes an atomic cell 2 (atomic cell), a light emitting unit 3, optical components 41, 42, 43, 44, a light detecting unit 5, a heater 6, a temperature, A sensor 7, a magnetic field generator 8, and a controller 10 are provided.

First, the principle of the atomic oscillator 1 will be briefly described.
As shown in FIG. 1, in the atomic oscillator 1, the light emitting unit 3 emits the excitation light LL toward the atomic cell 2, and the light detection unit 5 detects the excitation light LL transmitted through the atomic cell 2.

  A gaseous alkali metal (metal atom) is enclosed in the atomic cell 2, and the alkali metal has a three-level energy level and has different energy levels as shown in FIG. There can be three states: two ground states (ground states 1 and 2) and an excited state. Here, the ground state 1 is a lower energy state than the ground state 2.

The excitation light LL emitted from the light emitting unit 3 includes two types of resonance lights 1 and 2 having different frequencies. The two types of resonance lights 1 and 2 are irradiated onto the gaseous alkali metal as described above. Then, according to the difference (ω ₁ −ω ₂ ) between the frequency ω ₁ of the resonant light ₁ and the frequency ω ₂ of the resonant light 2, the light absorption rate (light transmittance) of the resonant light 1 and 2 in the alkali metal is increased. Change.

When the difference (ω ₁ −ω ₂ ) between the frequency ω ₁ of the resonant light ₁ and the frequency ω ₂ of the resonant light 2 coincides with the frequency corresponding to the energy difference between the ground state 1 and the ground state 2, the ground state Excitation from 1, 2 to the excited state stops. At this time, both the resonant lights 1 and 2 are transmitted without being absorbed by the alkali metal. Such a phenomenon is called a CPT phenomenon or an electromagnetically induced transparency (EIT) phenomenon.

For example, when the light emitting unit 3 fixes the frequency ω ₁ of the resonant light 1 and changes the frequency ω ₂ of the resonant light ₂ , the difference between the frequency ω ₁ of the resonant light ₁ and the frequency ω ₂ of the resonant light 2. When (ω ₁ −ω ₂ ) coincides with the frequency ω ₀ corresponding to the energy difference between the ground state 1 and the ground state 2, the detection intensity of the light detection unit 5 increases sharply as shown in FIG. . Such a steep signal is detected as an EIT signal. This EIT signal has an eigenvalue determined by the type of alkali metal. Therefore, an oscillator can be configured by using such an EIT signal.

Hereinafter, each part of the atomic oscillator 1 will be described sequentially.
[Atomic cell]
The atomic cell 2 is filled with gaseous alkali metals such as rubidium, cesium, and sodium. Further, in the atomic cell 2, a rare gas such as argon or neon, or an inert gas such as nitrogen may be sealed together with an alkali metal gas as a buffer gas, if necessary.

  The atomic cell 2 has a body portion having a through hole and a pair of light transmission portions that block the opening of the through hole of the body portion, thereby forming an internal space in which a gaseous alkali metal is enclosed. Has been. The atomic cell 2 will be described later in detail.

[Light emitting part]
The light emitting unit 3 (light source) has a function of emitting excitation light LL that excites alkali metal atoms in the atomic cell 2.

  More specifically, the light emitting unit 3 emits two types of light having different frequencies as described above as the excitation light LL, and can emit the above-described resonance light 1 and resonance light 2 in particular. . The resonant light 1 can excite (resonate) the alkali metal in the atomic cell 2 from the ground state 1 to the excited state. On the other hand, the resonant light 2 can excite (resonate) the alkali metal in the atomic cell 2 from the ground state 2 to the excited state.

  The light emitting unit 3 is not particularly limited as long as it can emit the excitation light as described above. For example, a semiconductor laser such as a vertical cavity surface emitting laser (VCSEL) can be used.

  The light emitting unit 3 is temperature adjusted to a predetermined temperature by a temperature adjusting element (a heating resistor, a Peltier element, etc.) (not shown).

[Optical parts]
The plurality of optical components 41, 42, 43, and 44 are respectively provided on the optical path of the excitation light LL between the light emitting unit 3 and the atomic cell 2 described above. Here, the optical component 41, the optical component 42, the optical component 43, and the optical component 44 are arranged in this order from the light emitting portion 3 side to the atomic cell 2 side.

  The optical component 41 is a lens. Thereby, the excitation light LL can be irradiated to the atomic cell 2 without waste.

  The optical component 41 has a function of making the excitation light LL a parallel light. Thereby, it is possible to easily prevent the excitation light LL from being reflected by the inner wall of the atomic cell 2. Therefore, resonance of excitation light in the atomic cell 2 is preferably generated, and as a result, the oscillation characteristics of the atomic oscillator 1 can be improved.

  The optical component 42 is a polarizing plate. Thereby, the polarization of the excitation light LL from the light emitting part 3 can be adjusted in a predetermined direction.

  The optical component 43 is a neutral density filter (ND filter). As a result, the intensity of the excitation light LL incident on the atomic cell 2 can be adjusted (decreased). Therefore, even when the output of the light emitting unit 3 is large, the excitation light incident on the atomic cell 2 can be set to a desired light amount. In the present embodiment, the optical component 43 adjusts the intensity of the excitation light LL having polarized light in a predetermined direction that has passed through the optical component 42 described above.

  The optical component 44 is a λ / 4 wavelength plate. Thereby, the excitation light LL from the light emitting unit 3 can be converted from linearly polarized light into circularly polarized light (right circularly polarized light or left circularly polarized light).

  As will be described later, if the alkali metal atom in the atomic cell 2 is Zeeman split by the magnetic field of the magnetic field generator 8, if the alkali metal atom is irradiated with linearly polarized excitation light, the interaction between the excitation light and the alkali metal atom As a result, the alkali metal atoms are present evenly dispersed in a plurality of Zeeman split levels. As a result, the number of alkali metal atoms at a desired energy level is relatively small with respect to the number of alkali metal atoms at other energy levels, so that the number of atoms that develop a desired EIT phenomenon is reduced and desired. As a result, the oscillation characteristics of the atomic oscillator 1 are deteriorated.

  On the other hand, when the alkali metal atom is irradiated with circularly polarized excitation light in a state where the alkali metal atom in the atomic cell 2 is Zeeman split by the magnetic field of the magnetic field generation unit 8 as described later, the excitation light, the alkali metal atom, The number of alkali metal atoms at a desired energy level is relatively larger than the number of alkali metal atoms at other energy levels among a plurality of levels in which the alkali metal atom is Zeeman split by the interaction of be able to. Therefore, the number of atoms that develop the desired EIT phenomenon increases, and the intensity of the desired EIT signal increases, and as a result, the oscillation characteristics of the atomic oscillator 1 can be improved.

[Photodetection section]
The light detection unit 5 has a function of detecting the intensity of the excitation light LL (resonance light 1 and 2) transmitted through the atomic cell 2.

  The photodetector 5 is not particularly limited as long as it can detect the excitation light as described above. For example, a photodetector (light receiving element) such as a solar cell or a photodiode can be used.

[heater]
The heater 6 (heating unit) has a function of heating the above-described atomic cell 2 (more specifically, an alkali metal in the atomic cell 2). Thereby, the alkali metal in the atomic cell 2 can be maintained in a gaseous state with an appropriate concentration.

  The heater 6 includes, for example, a heating resistor that generates heat when energized. The heating resistor may be provided in contact with the atomic cell 2 or may be provided in non-contact with the atomic cell 2.

For example, when the heating resistor is provided in contact with the atomic cell 2, the heating resistor is provided in each of the pair of light transmitting portions of the atomic cell 2. Thereby, it is possible to prevent the alkali metal atom from condensing on the light transmitting portion of the atomic cell 2. As a result, the characteristics (oscillation characteristics) of the atomic oscillator 1 can be made excellent over a long period of time. Such a heating resistor is a material having transparency to excitation light, specifically, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), In ₃ O ₃ , SnO ₂ , Sb-containing SnO _2. Further, it is made of a transparent electrode material such as an oxide such as Al-containing ZnO. The heating resistor can be formed using, for example, a chemical vapor deposition method (CVD) such as plasma CVD or thermal CVD, a dry plating method such as vacuum deposition, a sol-gel method, or the like.

  Further, when the heating resistor is provided in a non-contact manner with respect to the atomic cell 2, heat may be transferred from the heating resistor to the atomic cell 2 through a member such as a metal having excellent thermal conductivity, such as ceramic.

  The heater 6 is not limited to the above-described form as long as the atomic cell 2 can be heated, and various heaters can be used. Further, instead of the heater 6 or in combination with the heater 6, the atomic cell 2 may be heated using a Peltier element.

[Temperature sensor]
The temperature sensor 7 detects the temperature of the heater 6 or the atomic cell 2. Based on the detection result of the temperature sensor 7, the amount of heat generated by the heater 6 is controlled. Thereby, the alkali metal atom in the atomic cell 2 can be maintained at a desired temperature.

  The installation position of the temperature sensor 7 is not particularly limited, and may be, for example, on the heater 6 or on the outer surface of the atomic cell 2.

  The temperature sensor 7 is not particularly limited, and various known temperature sensors such as a thermistor and a thermocouple can be used.

[Magnetic field generator]
The magnetic field generator 8 has a function of generating a magnetic field that causes Zeeman splitting of a plurality of energy levels in which the alkali metal in the atomic cell 2 is degenerated. Thereby, by Zeeman splitting, the gap between different energy levels in which the alkali metal is degenerated can be widened to improve the resolution. As a result, the accuracy of the oscillation frequency of the atomic oscillator 1 can be increased.

  The magnetic field generator 8 is configured by, for example, a Helmholtz coil arranged so as to sandwich the atomic cell 2 or a solenoid coil arranged so as to cover the atomic cell 2. Thereby, a uniform magnetic field in one direction can be generated in the atomic cell 2.

  The magnetic field generated by the magnetic field generator 8 is a constant magnetic field (DC magnetic field), but an AC magnetic field may be superimposed.

[Control unit]
The control unit 10 has a function of controlling the light emitting unit 3, the heater 6, and the magnetic field generation unit 8.

  The control unit 10 includes an excitation light control unit 12 that controls the frequencies of the resonance lights 1 and 2 of the light emitting unit 3, a temperature control unit 11 that controls the temperature of the alkali metal in the atomic cell 2, and a magnetic field generation unit 8. And a magnetic field controller 13 for controlling the magnetic field from.

The excitation light control unit 12 controls the frequencies of the resonant lights 1 and 2 emitted from the light emitting unit 3 based on the detection result of the light detecting unit 5 described above. More specifically, the excitation light control unit 12 resonates the resonant light 1 emitted from the light emitting unit 3 so that the frequency difference (ω ₁ −ω ₂ ) described above becomes the frequency ω ₀ unique to the alkali metal described above. 2 frequency is controlled.

  Here, although not shown, the excitation light control unit 12 includes a voltage-controlled crystal oscillator (oscillation circuit), and the oscillation frequency of the voltage-controlled crystal oscillator is synchronized with the detection result of the light detection unit 5. While adjusting, the output signal of the voltage controlled crystal oscillator is output as the output signal of the atomic oscillator 1.

For example, although not shown, the pumping light control unit 12 includes a multiplier that multiplies the output signal from the voltage controlled crystal oscillator, and a signal (high frequency signal) multiplied by the multiplier is converted into a DC bias current. Is input to the light emitting unit 3 as a drive signal. Thus, by controlling the voltage controlled crystal oscillator so that the light detection unit 5 detects the EIT signal, a signal having a desired frequency is output from the voltage controlled crystal oscillator. The multiplication factor of this multiplier is, for example, ω ₀ / (2 × f), where f is the desired frequency of the output signal from the atomic oscillator 1. As a result, when the oscillation frequency of the voltage controlled crystal oscillator is f, a signal from the multiplier is used to modulate a light emitting element such as a semiconductor laser included in the light emitting unit 3 and a frequency difference (ω ₁ − _Two lights having ω ₂ ) of ω ₀ can be emitted.

  Further, the temperature control unit 11 controls energization to the heater 6 based on the detection result of the temperature sensor 7. Thereby, the atomic cell 2 can be maintained within a desired temperature range. For example, the temperature of the atomic cell 2 is adjusted to about 70 ° C. by the heater 6, for example.

  The magnetic field control unit 13 controls energization to the magnetic field generation unit 8 so that the magnetic field generated by the magnetic field generation unit 8 is constant, for example.

Such a control unit 10 is provided, for example, on an IC chip mounted on a substrate.
The configuration of the atomic oscillator 1 has been briefly described above.

(Detailed description of atomic cell)
FIG. 4 is a perspective view of an atomic cell provided in the atomic oscillator shown in FIG. 5A is a longitudinal sectional view of the atomic cell shown in FIG. 4, and FIG. 5B is a transverse sectional view of the atomic cell shown in FIG. FIG. 6 is a graph showing the relationship between the ratio of the thermal conductivity of the dissimilar material part to the thermal conductivity of the light transmission part and the frequency stability. In the following, for convenience of explanation, the upper side in FIG. 5A is referred to as “upper” and the lower side is referred to as “lower”.

  As shown in FIGS. 4 and 5, the atomic cell 2 includes a body part 21, a pair of light transmission parts 22 and 23 provided across the body part 21, and different types of elements arranged in the light transmission part 22. And a material portion 24. In this atomic cell 2, the body part 21 is disposed between the pair of light transmission parts 22, 23, and the body part 21 and the pair of light transmission parts 22, 23 are sealed with gaseous alkali metal. The internal space S is partitioned (configured).

  More specifically, the body portion 21 has a plate shape with the vertical direction as the thickness direction, and penetrates the body portion 21 in the thickness direction (vertical direction) of the body portion 21. Cylindrical through holes 211 and 212 and grooves 213 (concave portions) that are open on the upper surface of the body portion 21 and communicate with the through holes 211 and the through holes 212 are formed.

  The constituent material of the body portion 21 is not particularly limited, and examples thereof include a glass material, a crystal, a metal material, a resin material, a silicon material, and the like. It is preferable to use a glass material or a silicon material, and a light transmitting portion. It is preferable to use the same material (for example, glass material) as the constituent materials of 22 and 23. For example, by using a silicon material or a glass material as a constituent material of the body portion 21, even when forming a small atomic cell 2 having a width or height of 10 mm or less, a fine processing technique such as etching is used. It is possible to easily form the body portion 21 with high accuracy. In particular, when the constituent material of the body portion 21 is a glass material, the light transmitting portions 22 and 23 can be made of the same material as the light transmitting portions 22 and 23 while ensuring the light transmission properties of the light transmitting portions 22 and 23. The conductivity can be made lower than that of the different material portion 24 described later. In addition, for example, the surface activation method (SAB) or the atomic diffusion bonding method (ADB) can easily and hermetically bond the body portion 21 and the light transmission portions 22 and 23 both made of glass, The reliability of the cell 2 can be made excellent. Moreover, since these bonding methods can be bonded at a relatively low temperature (for example, room temperature), even if there is a difference in thermal expansion coefficient between the body portion 21 and the light transmitting portions 22 and 23, airtight bonding is possible. Is possible. Furthermore, these joining methods require a short time for joining. Therefore, the atomic cell 2 can be manufactured with high productivity.

  The light transmission part 22 is joined to the lower surface of the body part 21, while the light transmission part 23 is joined to the upper surface of the body part 21. Thereby, the lower end side openings of the through holes 211 and 212 are blocked by the light transmission part 22, and the upper end side openings of the through holes 211 and 212 and the opening of the groove 213 are blocked by the light transmission part 23.

  The joining method of the body part 21 and the light transmitting parts 22 and 23 is determined according to these constituent materials, and is not particularly limited as long as it can be hermetically joined. A bonding method, a direct bonding method, an anodic bonding method, a surface activated bonding method, or the like can be used.

  Each of the light transmission parts 22 and 23 joined to the body part 21 has transparency to the excitation light from the light emitting part 3 described above. One light transmission part 22 is an incident side light transmission part in which the excitation light LL enters the internal space S of the atomic cell 2, and the other light transmission part 23 is from the internal space S of the atomic cell 2. It is an emission side light transmission part from which the excitation light LL is emitted.

Further, each of the light transmitting portions 22 and 23 has a plate shape.
In the present embodiment, the light transmission part 22 is formed with a through hole 221 that penetrates in the thickness direction of the light transmission part 22 at a position corresponding to the through hole 212 of the body part 21. Thereby, the through-hole 212 and the through-hole 221 of the trunk | drum 21 are connecting. For example, as will be described later, the through-hole 221 is formed by forming a coating agent or an alkali metal (or a compound for generating an alkali metal) in the internal space S after forming the internal space S in the manufacturing process of the atomic cell 2. Can be used to introduce.

  The constituent material of the light transmitting portions 22 and 23 (substrate) is not particularly limited as long as it has transparency to the excitation light as described above, and examples thereof include glass materials and crystal. Is preferably used. Thereby, the light transmission parts 22 and 23 which have the transmittance | permeability with respect to excitation light are realizable. Further, when the body portion 21 is made of glass, the light transmitting portions 22 and 23 are made of glass, so that the surface activation method (SAB) and the atomic diffusion bonding method (ADB) can be used at a relatively low temperature. Thus, the body portion 21 and the light transmission portions 22 and 23 can be easily and airtightly joined, and the reliability of the atomic cell 2 can be improved. Even when the body portion 21 is made of silicon, the light transmission portions 22 and 23 are made of glass, so that the body portion 21 and the light transmission portions 22 and 23 can be easily airtight by anodic bonding. Thus, the reliability of the atomic cell 2 can be improved. Note that, depending on the thickness of the light transmitting portions 22 and 23 and the intensity of the excitation light, the light transmitting portions 22 and 23 can be made of silicon. In this case, the body part 21 and the light transmission parts 22 and 23 can be directly joined.

  The dissimilar material part 24 is arrange | positioned in the through-hole 221 of the light transmissive part 22 among such light transmissive parts 22 and 23. The through hole 221 is hermetically closed by the different material portion 24.

  In the internal space S sealed in this way, a gaseous alkali metal is mainly stored in a gas storage portion (hereinafter also simply referred to as “gas storage portion”) which is a space in the through hole 211. . The gaseous alkali metal stored in the gas storage unit is excited by the excitation light LL. That is, at least a part of the gas storage portion constitutes a “light passage space” through which the excitation light LL passes. In the present embodiment, the cross section of the through hole 211 is circular, has a shape similar to the cross section of the light passage space (that is, a circle), and is set slightly larger than the cross section of the light passage space. Yes. The cross-sectional shape of the through hole 211 is not limited to a circle, and may be, for example, a polygon such as a quadrangle or a pentagon, an ellipse, or the like.

  In addition, a metal reservoir portion (hereinafter, also simply referred to as “metal reservoir portion”) that is a space in the through hole 212 (including a space above the dissimilar material portion 24 in the through hole 221) is a space in the groove 213. And communicates with the space in the through-hole 211 through which a liquid or solid alkali metal M is stored. More specifically, a liquid or solid alkali metal M is disposed on the dissimilar material portion 24 in the metal reservoir. In the present embodiment, each of the through holes 212 and 221 has a circular cross section. In addition, the cross-sectional shape of the through holes 212 and 221 is not limited to a circle, and may be a polygon such as a quadrangle or a pentagon, an ellipse, or the like. Further, the cross-sectional shape of the through hole 212 and the cross-sectional shape of the through hole 221 may be different from each other.

  In addition, the through hole 221 has a diameter of a portion opposite to the through hole 212 and has a stepped portion 2211 formed therein. The dissimilar material portion 24 is disposed in the enlarged diameter portion of the through hole 221 and is airtightly joined to the step portion 2211. As described above, by using the stepped portion 2211 as a joint surface with the dissimilar material portion 24, the inside of the through hole 221 can be hermetically closed without matching the width of the through hole 221 and the width of the dissimilar material portion 24. The dissimilar material part 24 can be easily and reliably joined to the wall surface of the through hole 221. In the figure, the dissimilar material portion 24 has a shape that matches the diameter-expanded portion of the through-hole 221, but the shape is arbitrary as long as the through-hole 221 can be hermetically closed.

  The dissimilar material part 24 is made of a material having a higher thermal conductivity than the light transmission parts 22 and 23. As a result, the dissimilar material portion 24 is easier to dissipate heat than the light transmitting portions 22 and 23. Therefore, the temperature of the dissimilar material portion 24 can be made lower than that of the light transmitting portions 22 and 23. As a result, liquid or solid alkali metal atoms are condensed and attached to the light transmitting portions 22 and 23. Can be prevented or reduced. Conversely, liquid or solid alkali metal atoms can be easily condensed in the vicinity of the dissimilar material portion 24, and the inside of the through hole 212 can be made a “metal reservoir portion”. Therefore, the dissimilar material portion 24 is disposed between the metal reservoir portion and the outside of the internal space S.

  Thus, by making the thermal conductivity of the constituent material of the dissimilar material portion 24 larger than the thermal conductivity of the light transmitting portions 22 and 23, the frequency stability can be improved as shown in FIG.

  Further, the dissimilar material portion 24 faces the inside and outside of the internal space S. Thereby, heat can be easily radiated from the inside of the internal space S to the outside via the dissimilar material portion 24.

  Here, there are three forms of heat dissipation (heat transfer) from the atomic cell 2: heat conduction, convective heat transfer, and heat radiation (radiation). In general, from the viewpoint of reducing a decrease in frequency stability due to temperature fluctuations of the atomic cell 2, for example, the atomic cell 2 is used by being housed in a decompressed package so that heat escape due to convective heat transfer is reduced. It is done. Further, when the atomic cell 2 is housed in the package in this way, the thermal resistance of the member that supports the atomic cell 2 with respect to the package is increased, and the heat escape due to heat conduction is reduced.

  In such a case, it is preferable that the dissimilar material part 24 is connected to a member that supports the atomic cell 2 from the viewpoint of improving heat dissipation from the dissimilar material part 24. In addition, from the viewpoint of improving heat dissipation by heat radiation from the dissimilar material part 24, it is preferable that the emissivity of the dissimilar material part 24 is larger than the emissivities of the light transmitting parts 22 and 23.

  The material of the dissimilar material part 24 is not particularly limited as long as it has a higher thermal conductivity than the material of the light transmitting parts 22 and 23, but an inorganic material is suitable from the viewpoint of chemical stability. In addition, the constituent material of the dissimilar material portion 24 is preferably capable of hermetic sealing with a low reactivity with the alkali metal from the viewpoint of stably maintaining the state of the alkali metal in the internal space S over a long period of time. For example, a silicon material is preferable. When the light transmitting portion 22 includes glass, the dissimilar material portion 24 includes silicon, so that the dissimilar material portion 24 and its peripheral portion (light transmitting portion 22) are directly bonded (solid bonding) by anodic bonding. It can be easily and firmly joined. Further, since the light-transmitting portion 22 and the dissimilar material portion 24 can be hermetically bonded, the dissimilar material portion 24 is used for sealing the sealing hole (through hole 221) as in the present embodiment. However, the airtightness of the internal space S can be made excellent. In addition, the joining method of the dissimilar material part 24 and its peripheral part is determined according to the constituent material of the dissimilar material part 24 and its peripheral part, and is not limited to the above-described one. A sealing method, a surface activated bonding method, or the like may be used.

  Further, as the constituent material of the different material portion 24, it is preferable that the thermal conductivity is higher than that of the constituent material of the body portion 21 as well as the constituent material of the light transmitting portions 22 and 23. As a result, the condensation of liquid or solid alkali metal on the wall surface of the through hole 211 can be reduced, and the liquid or solid alkali metal can be easily present in the through hole 212 (metal reservoir). it can.

  The inner wall surface of the internal space S is coated. That is, the coating film 25 is formed on the inner wall surface of the internal space S.

  The coating film 25 has a function of suppressing or reducing a change in behavior (for example, spin) when a gaseous alkali metal collides with the inner wall surface of the internal space S. As a result, even if the atomic cell 2 is downsized, the change in behavior caused by the alkali metal colliding with the inner wall surface of the atomic cell 2 is prevented from adversely affecting the characteristics, and the oscillation characteristics of the atomic oscillator 1 are excellent. It can be.

  The constituent material of the coating film 25 preferably contains a fluorine-based resin, a siloxane-based compound, or a chain saturated hydrocarbon. Thereby, the change in behavior when the alkali metal collides with the coating film 25 can be effectively reduced, and the chemical stability is excellent. Moreover, the boiling point of the coating material can be made higher than the boiling point of the metal atom.

  According to the atomic cell 2 as described above, since the thermal conductivity of the dissimilar material portion 24 is larger than that of the light transmitting portions 22 and 23, the dissimilar material portion 24 is easier to dissipate heat than the light transmitting portions 22 and 23. Become. Therefore, the temperature of the dissimilar material portion 24 can be made lower than that of the light transmitting portions 22 and 23. As a result, liquid or solid alkali metal atoms are condensed and attached to the light transmitting portions 22 and 23. Can be prevented or reduced. Therefore, frequency stability can be improved.

  Further, in the present embodiment, as shown in FIG. 5A, a partition wall 210 (wall) is provided between the gas storage part and the metal reservoir (between the through hole 211 and the through hole 212). Has been placed. Thereby, it can reduce that a liquid or solid alkali metal atom moves to a gas storage part from a metal reservoir part. As a result, the frequency stability can be further improved.

  In addition, since the dissimilar material portion 24 is disposed in the light transmission portion 22 in such an atomic cell 2, a plurality of light transmission portions 22 and 23 and a plurality of body portions 21 for forming a body portion 21 are formed as described later. When the atomic cell 2 is formed by bonding the substrates, the formation of the dissimilar material portion 24 can be simplified.

(Atom cell manufacturing method)
Hereinafter, an example of the manufacturing method of the atomic cell 2 described above will be described. In the following, an example will be described in which each of the body portion 21 and the light transmission portions 22 and 23 is made of glass, and the dissimilar material portion 24 is made of silicon.
7 and 8 are views for explaining a method of manufacturing the atomic cell shown in FIG.

  The manufacturing method of the atomic cell 2 includes [1] preparation step, [2] bonding step, [3] coating step, [4] metal compound placement step, [5] sealing step, and [6] alkali. A metal generation step. Hereinafter, each process is demonstrated one by one.

[1] Preparation Step First, as shown in FIG. 7A, the body portion 21 and the light transmission portions 22 and 23 are prepared.

  Formation of the through holes 211 and 212 and the groove 213 of the body part 21 and the through hole 221 of the light transmission part 22 can be performed using, for example, an etching technique or a photolithography technique.

  In addition, it replaces with the trunk | drum 21 and the light transmissive parts 22 and 23, and is a glass substrate for forming the trunk | drum 21, Comprising: The trunk | drum part formation board | substrate which has two or more sets of through-holes 211 and 212, and the groove | channel 213, Light transmissive part A glass substrate for forming 22 and a light transmitting portion forming substrate having a plurality of through holes 221 and a light transmitting portion forming substrate for forming the light transmitting portion 23 may be prepared. In this case, the body part 21 and the light transmitting parts 22 and 23 can be formed by joining these substrates in the joining process [2] and separating them after the sealing process [5].

[2] Joining Step Next, as shown in FIG. 7B, the body portion 21 and the light transmitting portions 22, 23 are joined. Thereby, a structure having the internal space S is obtained. In this structure, the internal space S communicates with the outside through the through hole 221.

  The body portion 21 and the light transmitting portions 22 and 23 are preferably joined by a surface activation method (SAB) or an atomic diffusion bonding method (ADB). Thereby, the trunk | drum 21 and the light transmissive parts 22 and 23 can be airtightly joined comparatively easily at comparatively low temperature.

[3] Coating Step Next, as shown in FIG. 7C, the coating material is fed into the internal space S through the through hole 221. Thereby, the coating film 25 is formed.

  More specifically, a gaseous coating material (coating material gas) is fed into the internal space S through the through hole 221. The wall surface of the internal space S is cooled below the boiling point (more preferably below the melting point) of the coating material. Thereby, the gaseous coating material condenses or solidifies on the wall surface of the internal space S to form the coating film 25.

  The coating material is not particularly limited as long as it can form the coating film 25 having the above-described function, but any one of a fluorine-based resin, a siloxane-based compound, and a chain saturated hydrocarbon is used. Or a precursor thereof.

  The coating film 25 obtained from such a compound can effectively reduce the change in behavior when the alkali metal collides, and is excellent in chemical stability.

  Examples of the fluororesin used as a coating material include polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), and perfluoroalkoxy fluororesin (PFA). , Tetrafluoroethylene / hexafluoropropylene copolymer (FEP), ethylene / tetrafluoroethylene copolymer (ETFE), ethylene / chlorotrifluoroethylene copolymer (ECTFE), and the like.

  Examples of the siloxane compound used as a coating material include methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, hexyltrimethoxysilane, and hexyltri Examples thereof include alkoxysilanes such as ethoxysilane, decyltrimethoxysilane and trifluoropropyltrimethoxysilane, silazanes such as hexamethyldisilazane, and siloxanes such as hydrolyzable group-containing siloxane.

  Examples of the chain saturated hydrocarbon used as the coating material include paraffin (an alkane having 20 or more carbon atoms).

  When the coating material is a precursor of the constituent material of the coating film 25, the condensed or solidified coating material is reacted with the wall surface of the internal space S by heating or the like as necessary.

[4] Metal Compound Arrangement Step Next, as shown in FIG. 8A, the metal compound P is arranged in the through hole 212. At this time, although not shown, a getter material or a reducing agent necessary for the decomposition reaction of the metal compound P is disposed in the through hole 221 as necessary.

The metal compound P is a compound containing an alkali metal, and is a compound that generates (releases) a single alkali metal by a decomposition reaction (reduction). The metal compound P is not particularly limited as long as it is a compound that generates a single alkali metal by a decomposition reaction (reduction). For example, cesium chloride (CsCl), cesium azide (CsN ₃ ) cesium chromate (CsCr) ₂ O ₇ ) and the like. Here, the metal compound P does not substantially cause a decomposition reaction under heating in the [5] sealing step described later, that is, the temperature at which the decomposition reaction occurs is higher than the heating temperature in the [5] sealing step. It is preferable. Thereby, it can prevent or reduce that an alkali metal adheres to the joint surface of the light transmissive part 22 and the dissimilar material part 24. FIG.

  Moreover, the reducing agent used for the decomposition reaction of the metal compound P is not particularly limited. For example, when the metal compound P is cesium chloride, calcium is used. In addition, this reducing agent may be separate from the metal compound P, or may be integrated as a mixture or aggregate with the metal compound P.

  The getter material has a function of adsorbing or absorbing a gas other than the desired alkali metal gas and buffer gas. The getter material is not particularly limited as long as it has such a function. For example, an alloy containing at least one of titanium, barium, tantalum, zirconium, aluminum, vanadium, indium, and calcium, or Al- Zr—V—Fe based alloys can be mentioned. By using such a getter material, it is possible to adsorb or absorb the gaseous unnecessary matter in the internal space S after the [5] sealing step described later. The getter material may be a separate body from the metal compound P, or may be integrated as a mixture or aggregate with the metal compound P.

[5] Sealing Step Next, as shown in FIG. 8B, the dissimilar material part 24 is placed in the through hole 221, and the dissimilar material part 24 and the light transmitting part 22 are joined by the anodic bonding method. . Thereby, the through-hole 221 is hermetically closed by the dissimilar material part 24, and the internal space S which is an airtight space is formed.

  Here, at the time of anodic bonding, the bonding portion becomes high temperature, but since the bonding portion is local, it is possible to reduce melting of the coating film 25 by locally performing heating only at a necessary portion. Can do. Thereby, in the atomic cell 2 finally obtained, the uniformity of the coating film 25 can be improved.

[6] Alkali Metal Generation Step Next, as shown in FIG. 8C, the metal compound P is irradiated with a laser (energy beam). Thereby, the alkali metal simple substance is taken out by decomposing the metal compound P.

  At this time, a reaction product other than the alkali metal is generated by the decomposition reaction of the metal compound P, and an unreacted metal compound P remains as a residue, although not shown.

Specifically, for example, when the metal compound P is cesium chloride and calcium is used as the reducing agent,
In this step, a reaction of 2CsCl + Ca → 2Cs ↑ + CaCl ₂ occurs. Thus, cesium can be taken out as a simple substance by reducing cesium chloride using calcium as a reducing agent. Therefore, cesium atoms can be enclosed in the atomic cell 2.

When the metal compound P is cesium azide,
In this step, a reaction of 2CsN ₃ → 2Cs + 3N ₂ occurs. Thus, cesium can be taken out as a simple substance by reducing cesium azide. Therefore, cesium atoms can be enclosed in the atomic cell 2.

  In this step, since the decomposition reaction is caused by irradiating the metal compound P with energy rays, the metal compound P disposed in the sealed internal space S can be decomposed. In FIG. 8C, the case where the decomposition reaction of the metal compound P is caused by using a laser is illustrated as an example. However, as long as the decomposition reaction of the metal compound P can be caused, the invention is not limited to the laser. Examples thereof include light other than laser, electromagnetic waves such as X-rays and γ-rays, electron beams, particle beams such as ion beams, and the like, or combinations of two or more of these energy beams. Further, the metal compound P may be heated by electromagnetic induction to cause a decomposition reaction.

  According to the manufacturing method of the atomic cell 2 as described above, the atomic cell 2 having the effects described above can be obtained. The method for manufacturing the atomic cell 2 is not limited to the above-described method. For example, after introducing a liquid or solid alkali metal into the internal space S from the through-hole 221 without using the metal compound P, different types of materials can be used. The through hole 221 may be blocked by the material portion 24.

Second Embodiment
Next, a second embodiment of the present invention will be described.

  FIG. 9A is a longitudinal sectional view showing an atomic cell according to the second embodiment of the present invention, and FIG. 9B is a transverse sectional view of the atomic cell shown in FIG. 9A.

  This embodiment is the same as the first embodiment described above, except that the atomic cell has two metal reservoirs and two different material parts.

  In the following description, the second embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

  An atomic cell 2A (atomic cell) shown in FIG. 9 includes a body part 21A and a light transmission part 23A instead of the body part 21 and the light transmission part 23 of the first embodiment. In addition, the atomic cell 2A includes a dissimilar material portion 26 disposed in the light transmission portion 23A.

  The body portion 21A has a plate shape. The body portion 21A includes through holes 211, 212, and 214 that pass through in the thickness direction (vertical direction) of the body portion 21A, and an upper surface of the body portion 21A. A groove 213 (concave portion) that opens and communicates with the through hole 211 and the through hole 212, and a groove 215 that opens on the lower surface of the body portion 21 and communicates the through hole 211 and the through hole 214 ( A recess).

  The light transmitting portion 22 is joined to the lower surface of the body portion 21A, and the light transmitting portion 23A configured similarly to the light transmitting portion 22 is joined to the upper surface of the body portion 21A.

  Here, a through hole 231 that penetrates in the thickness direction of the light transmitting portion 23A is formed in the light transmitting portion 23A at a position corresponding to the through hole 214 of the body portion 21A. Thereby, the through-hole 214 and the through-hole 231 of the trunk | drum 21A are connecting. The through-hole 231 is similar to the through-hole 221 of the light transmission part 22, for example, after forming the internal space S in the manufacturing process of the atomic cell 2 </ b> A, a coating agent or an alkali metal (or alkali metal is generated in the internal space S). Can be used to introduce a compound).

  By providing the two through holes 221 and 231 as described above, for example, when forming the coating film 25, the coating agent can be introduced from one through hole and the coating can be discharged from the other through hole. Therefore, the coating film 25 can be formed by smoothly introducing the coating agent into the internal space S without depressurizing the internal space S. Further, after the formation of the coating film 25, the through hole 231 is closed by the different material portion 26, and thereafter, an alkali metal can be introduced into the internal space S as in the first embodiment described above.

  In the present embodiment, the dissimilar material part 26 does not necessarily have to have a thermal conductivity higher than that of the light transmitting parts 22 and 23A.

  Even with the atomic cell 2A according to the second embodiment as described above, the frequency stability can be improved.

<Third Embodiment>
Next, a third embodiment of the present invention will be described.
FIG. 10 is a longitudinal sectional view showing an atomic cell according to the third embodiment of the present invention.

  This embodiment is the same as the first embodiment described above except that the atomic cell has two different material portions.

  In the following description, the third embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

  An atomic cell 2B (atomic cell) shown in FIG. 10 includes a light transmission portion 23A instead of the light transmission portion 23 of the first embodiment. In addition, the atomic cell 2B includes a dissimilar material portion 26 disposed in the light transmission portion 23A.

  Here, a through hole 231 that penetrates in the thickness direction of the light transmitting portion 23A is formed in the light transmitting portion 23A at a position corresponding to the through hole 212 of the body portion 21. Thereby, the through-hole 212 and the through-hole 231 of the trunk | drum 21 are connecting. This through hole 231 is similar to the through hole 221 of the light transmitting portion 22, for example, in the process of manufacturing the atomic cell 2 </ b> B, after forming the internal space S, a coating agent or alkali metal (or alkali metal is generated in the internal space S. Can be used to introduce a compound).

  By providing the two through holes 221 and 231 as described above, for example, when forming the coating film 25, the coating agent is introduced from one through hole while the other through hole is formed, as in the second embodiment described above. The coating can be discharged from.

  Even with the atomic cell 2B according to the third embodiment as described above, the frequency stability can be improved.

<Fourth embodiment>
Next, a fourth embodiment of the present invention will be described.

  FIG. 11A is a longitudinal sectional view showing an atomic cell according to the fourth embodiment of the present invention, and FIG. 11B is a transverse sectional view of the atomic cell shown in FIG. 11A.

  The present embodiment is the same as the first embodiment described above except that the configuration of the metal reservoir and the dissimilar material portion of the atomic cell is different.

  In the following description, the fourth embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

  An atomic cell 2C (atomic cell) shown in FIG. 11 has a plate-shaped body portion 21C having a through groove 211C penetrating in the thickness direction (vertical direction) and a pair of light transmissions that block the upper and lower openings of the through groove 211C. It has parts 22C and 23C, and a dissimilar material part 24C that closes the opening on the side of the through groove 211C. Here, the through groove 211 </ b> C has an opening 216 that opens to the side, and the dissimilar material portion 24 </ b> C is formed between the stepped portion 2161 formed in the opening 216 and the side surfaces 222 and 232 of the light transmitting portions 22 </ b> C and 23 </ b> C. It is airtightly joined.

  As described above, the dissimilar material portion 24C is arranged in the body portion 21C, whereby the atomic cell 2C can be reduced in size.

  Even with the atomic cell 2C according to the fourth embodiment as described above, the frequency stability can be improved.

2. Electronic equipment The atomic oscillator described above can be incorporated into various electronic equipment. Such an electronic device has excellent reliability.

Hereinafter, the electronic apparatus of the present invention will be described.
FIG. 12 is a diagram showing a schematic configuration when the atomic oscillator of the present invention is used in a positioning system using a GPS satellite.

  The positioning system 100 shown in FIG. 12 includes a GPS satellite 200, a base station device 300, and a GPS receiver 400.

The GPS satellite 200 transmits positioning information (GPS signal).
The base station device 300 receives the positioning information from the GPS satellite 200 with high accuracy via, for example, an antenna 301 installed at an electronic reference point (GPS continuous observation station), and the reception device 302 receives the positioning information. And a transmission device 304 that transmits positioning information via the antenna 303.

  Here, the receiving device 302 is an electronic device provided with the above-described atomic oscillator 1 of the present invention as its reference frequency oscillation source. Such a receiving apparatus 302 has excellent reliability. In addition, the positioning information received by the receiving device 302 is transmitted by the transmitting device 304 in real time.

  The GPS receiver 400 includes a satellite receiver 402 that receives positioning information from the GPS satellite 200 via the antenna 401, and a base station receiver 404 that receives positioning information from the base station device 300 via the antenna 403. Prepare.

3. Mobile Object FIG. 13 is a diagram showing an example of a mobile object of the present invention.

In this figure, a moving body 1500 has a vehicle body 1501 and four wheels 1502, and is configured to rotate the wheels 1502 by a power source (engine) (not shown) provided in the vehicle body 1501. In such a moving body 1500, the atomic oscillator 1 is built.
According to such a moving body, excellent reliability can be exhibited.

  Note that the electronic apparatus of the present invention is not limited to the above-described ones. For example, a mobile phone, a smartphone, a tablet terminal, a watch, a digital still camera, an ink jet discharge device (for example, an ink jet printer), a personal computer (a mobile personal computer) , Laptop personal computer), TV, video camera, video tape recorder, car navigation device, pager, electronic organizer (including communication function), electronic dictionary, calculator, electronic game device, word processor, workstation, video phone, TV monitor for crime prevention, electronic binoculars, POS terminal, medical equipment (for example, electronic thermometer, blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish detector, various measuring devices, instruments ( Example If, vehicle, aircraft, gauges of a ship), flight simulators, terrestrial digital broadcasting, can be applied to a mobile phone base station or the like.

  As described above, the atomic cell, the quantum interference device, the atomic oscillator, the electronic device, and the moving body of the present invention have been described based on the illustrated embodiments, but the present invention is not limited to these.

  In addition, the configuration of each part of the present invention can be replaced with any configuration that exhibits the same function as that of the above-described embodiment, and any configuration can be added.

  Moreover, you may make it this invention combine arbitrary structures of each embodiment mentioned above.

  In the above-described embodiment, the case where the atomic cell of the present invention is used in a quantum interference device that resonantly transitions cesium or the like using the quantum interference effect of two types of light having different wavelengths has been described as an example. The atomic cell of the invention is not limited to this, and can also be used for a double resonance apparatus that makes a resonance transition of rubidium or the like by utilizing a double resonance phenomenon caused by light and microwaves.

DESCRIPTION OF SYMBOLS 1 ... Atomic oscillator 2 ... Atomic cell 2A ... Atomic cell 2B ... Atomic cell 2C ... Atomic cell 3 ... Light emitting part 5 ... Light detection part 6 ... Heater 7 ... Temperature sensor 8 ... Magnetic field Generation unit 10 ... Control unit 11 ... Temperature control unit 12 ... Excitation light control unit 13 ... Magnetic field control unit 21 ... Body part 21A ... Body part 21C ... Body part 22 ... Light transmission part 22C ... Light transmission part 23 ... Light transmission part 23A ... Light transmission part 23C ... Light transmission part 24 ... Dissimilar material part 24C ... Dissimilar material part 25 ... Coating film 26 ... Dissimilar material part 41 ... Optical component 42 Optical component 43 Optical component 44 Optical component 100 Positioning system 200 GPS satellite 210 Bulkhead portion 211 Through hole 211C Through groove 212 Through hole 213 Through groove 214 ... through hole 215 ... groove 216 ... opening 22 Through hole 222 Side surface 231 Through hole 232 Side surface 300 Base station device 301 Antenna 302 Reception device 303 Antenna 304 Transmission device 400 GPS reception device 401 Antenna 402 ··· Satellite receiver 403 ··· Antenna 404 ··· Base station receiver 1500 · · · Mobile body 1501 · · · Body 1502 · · · Wheel 2161 · · · Step portion 2211 · · · Step portion M · · · Alkali metal S · · · Internal Space LL ... Excitation light P ... Metal compound

Claims (11)

Metal atoms,
A pair of light transmission parts;
A body part that constitutes an internal space containing the metal atoms together with the pair of light transmission parts;
A dissimilar material part including a material having a higher thermal conductivity than the light transmission part;
With
The internal space has a metal reservoir that stores the metal atom in a liquid or solid state,
The atomic cell, wherein the dissimilar material part is disposed between the outside of the internal space and the metal reservoir part.   The atomic cell according to claim 1, wherein the dissimilar material portion faces inside and outside the internal space.   The atomic cell according to claim 1, wherein the dissimilar material part is disposed in the light transmission part. The internal space has a gas storage part that stores the gaseous metal atoms,
The atomic cell according to claim 1, wherein a wall portion is disposed between the gas storage portion and the metal reservoir portion. The light transmitting portion includes glass;
The atomic cell according to claim 1, wherein the different material portion includes silicon.   The atomic cell according to claim 1, wherein the dissimilar material part is disposed in the body part.   The atomic cell according to claim 1, wherein the dissimilar material part and its peripheral part are directly joined.   A quantum interference device comprising the atomic cell according to claim 1.   An atomic oscillator comprising the atomic cell according to claim 1.   An electronic apparatus comprising the atomic cell according to claim 1.   A moving body comprising the atomic cell according to any one of claims 1 to 7.

Images