CN103454902B - A kind of atomic clock - Google Patents
A kind of atomic clock Download PDFInfo
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- CN103454902B CN103454902B CN201310252462.8A CN201310252462A CN103454902B CN 103454902 B CN103454902 B CN 103454902B CN 201310252462 A CN201310252462 A CN 201310252462A CN 103454902 B CN103454902 B CN 103454902B
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- atomic clock
- photodetector
- fiber
- air chamber
- laser instrument
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Abstract
The invention discloses a kind of atomic clock, be made up of electronic system and physical package, described physical package comprises laser instrument, conversion light path, quarter wave plate, basic atom bubble air chamber and photodetector, it is characterized in that: four anti-films of optical fiber, GRIN Lens and increasing that described conversion light path comprises four fiber port coupling mechanisms, is connected with fiber coupler, the output terminal of described laser instrument connects the first optical fiber, second Fiber connection GRIN Lens, the 3rd Fiber connection photodetector; The anti-film of described increasing is positioned at the exiting side of basic atom bubble air chamber, emergent light is reflected back basic atom bubble air chamber.The present invention can make laser instrument and photodetector steep air chamber away from basic atom, and the degree of stability of atomic clock, on its impact, is improved in minimizing temperature and magnetic field.
Description
Technical field
The present invention relates to a kind of atomic clock, belong to frequency standard device field.
Background technology
The developing history of atomic clock can be traced back to before and after World War II the earliest, and it mainly has benefited from the fast development of quantum mechanics and microwave spectroscopy at that time.Early stage microwave clock uses incoherent light source to do pumping and detection light, and thereafter along with the development of laser instrument, Laser Coherent and detection method are applied in atomic clock research, obtain better effect.
Along with the develop rapidly of electronic technology and control technology, the research for atomic clock mainly concentrates on two aspects: be explore development accuracy and the higher atomic clock of degree of stability on the one hand.In recent years, many different types of New type atom clocks possessing more pin-point accuracy and degree of stability have successfully been developed, such as Cold atomic fountain clock, ion trap clock, light clock etc.; Actively find the approach realizing high-precision mini engineering atomic clock on the other hand, to meet various engineering development needs, such as develop small-sized satellite atomic clock, utilize Coherent Population Trapping imprison principle to develop Miniaturized Coherent Population Trapping imprison (CPT, CoherentPopulationTrapping) atomic clock.
Coherent Population Trapping imprison is a kind of quantum interference phenomenon that atom and coherent light interaction produce, utilize the coherence that laser is good, Coherent Population Trapping imprison state is prepared in atom system, the novel C PT atomic clock of the chip type that can realize, this is the cutting edge technology of current atomic clock field and navigation field.Its advantage is: on the one hand, does not need microwave cavity, obviously can reduce volume; On the other hand, adopt the relevant bi-coloured light of laser instrument preparation by microwave frequency modulation, can optical frequency shift be reduced.Although CPT atomic clock proposed the time so far from 1998, its development rapidly, has demonstrated superior performance, and also has larger room for improvement also soon.
In prior art, CPT atomic clock comprises electronic system and physical package, wherein, physical package is made up of laser instrument, conversion light path, quarter wave plate, basic atom bubble air chamber and photodetector usually, the laser that laser instrument sends converts directional light to by changing light path, formed after entelechy polarized light through quarter wave plate and enter basic atom bubble air chamber, finally received by photoconductive detector.Wherein, change light path and be generally lens combination.
Evaluate performance index mainly Alan's variance of atomic clock.According to the definition of Alan's variance, the performance of known atomic clock depends primarily on the contrast of absorption line.
In practice, general CPT tabletop experiments system only pursues the aspect of commissioning, does not consider the problem of volume and power consumption, and the minimizing of volume and power consumption focused on really by miniature and even chip-scale CPT atomic clock very much, but inconvenient commissioning.Up to the present realized CPT atomic clock index is not very high, is mainly manifested in temperature drift phenomenon relatively more serious, and temperature control causes power consumption comparatively large, and atomic clock stable output signal degree is very low.Its main cause is packaged together by each part mentioned above in prior art, and because basic atom bubble is under air chamber remains on the working temperature of 70 ~ 90 DEG C usually, laser instrument and photodetector and basic atom steep the close together of air chamber, can be subject to the impact of its temperature,
Therefore, need the improvement by structure, reduce temperature drift phenomenon, thus reduce the error of atomic clock.
Summary of the invention
Goal of the invention of the present invention is to provide a kind of atomic clock, is improved by structure, reduces temperature to the impact of atomic clock.
To achieve the above object of the invention, the technical solution used in the present invention is: a kind of atomic clock, is made up of electronic system and physical package, and described physical package comprises laser instrument, conversion light path, quarter wave plate, basic atom bubble air chamber and photodetector; Four anti-films of optical fiber, GRIN Lens and increasing that described conversion light path comprises four fiber port coupling mechanisms, is connected with fiber coupler, the output terminal of described laser instrument connects the first optical fiber, the second Fiber connection GRIN Lens, the 3rd Fiber connection photodetector; The anti-film of described increasing is positioned at the exiting side of basic atom bubble air chamber, emergent light is reflected back basic atom bubble air chamber.
In technique scheme, described laser instrument is for optical gain medium with direct band-gap semicondictor material, inject charge carrier by pn knot and realize population inversion, with Fabry-Perot-type cavity or distribution bragg grating for resonator cavity, carry out the diode laser of stimulated emission light amplification.
Described four fiber port coupling mechanisms are 2 × 2 single-mode optical-fibre couplers.
Described GRIN Lens is that inner refractive index distributes the lens pillar radially reduced gradually.
The thickness of the anti-film of described increasing equals 1/4th optical maser wavelengths.
Further technical scheme, is provided with the second photodetector, and described second photodetector connects the 4th optical fiber.
Preferred technical scheme is, described basic atom bubble air chamber is arranged in different individual packages from described laser instrument, photodetector.
In technique scheme, described electronic system comprises phase-locked loop, electrically controlled attenuator, micro control system and analog-digital chip, in order to control wavelength and the frequency of laser instrument.
Adopt caesium chamber for basic atom bubble air chamber, principle of work of the present invention is explained as follows: laser instrument sends laser, and is modulated on the left and right sideband of laser by the 4.596GHz microwave signal that phase-locked loop produces, and laser is radiated on caesium chamber; 2 × 2 fiber couplers between laser instrument and caesium chamber, be attached thereto connect have four optical fiber.Wherein the second optical fiber is connected with GRIN Lens, places one block of quarter-wave plate, laser beam is transformed into circularly polarized light and is irradiated into caesium chamber after GRIN Lens; Connect behind caesium chamber and increase anti-film, light path, through increasing the reflection of anti-film, enters fiber coupler again, and is exported by the 3rd optical fiber; Connect photodetector at output port, light signal is converted to current signal by photodetector, and by micro control system extraction process, micro control system will produce control signal further, until whole atomic clock system is in the lock state.
In further technical scheme, connect the second photodetector at the 4th fiber port of fiber coupler, be used for the incident intensity of detecting laser.
In such scheme, Laser Modulation mode adopts half-band width to modulate, namely RF modulating frequency equals the differential half of two Ground State Energies, and it is poor that the difference of first sideband frequency in left and right then just equals the hyperfine energy level splitting of ground state, realizes CPT resonance by these two single order sideband pump excitations.This modulator approach is defined as half-breadth modulation.
Because technique scheme is used, the present invention compared with prior art has following advantages:
1, the present invention is by arranging the fiber coupler of four ports, arrange simultaneously and increase anti-film, laser instrument is connected with fiber coupler respectively with photodetector, laser instrument and photodetector can be made to steep air chamber away from basic atom, minimizing temperature and magnetic field are on its impact.
2, owing to adopting optical fiber and fiber coupler to form conversion light path, the loss of light can be reduced.
3, the setting of anti-film is increased, photodetector is made to be connected on fiber coupler together with laser instrument on the one hand, basic atom bubble air chamber is entered on the other hand by again being reflected by emergent light, light path can be increased, make light follow the action time of Cs atom or rubidium atom elongated, improve the degree of stability of atomic clock.
4, the setting of the second photodetector, can the incident intensity of detecting laser, so that the light intensity change of observation laser in time.
Accompanying drawing explanation
Fig. 1 is embodiment Central Plains secondary clock overall system diagram.
Fig. 2 is phase-locked loop system block diagram in embodiment.
Fig. 3 is the laser aligner index path that in embodiment, GRIN Lens and optical fiber form.
Fig. 4 is caesium in atomic clock physical package/rubidium chamber atmo energy level transition figure.
Fig. 5 is embodiment loop filter circuit diagram.
Embodiment
Below in conjunction with drawings and Examples, the invention will be further described:
Embodiment 1:
As shown in Figure 1, a kind of atomic clock with GRIN Lens, mainly comprises laser instrument 170, fiber coupler 120 and be attached thereto four optical fiber 121,122,123,124 connect, GRIN Lens 130, quarter-wave plate 140, caesium chamber 150, increase anti-film 160, photodetector 110 and the second photodetector 180, phase-locked loop 200, electrically controlled attenuator 300, micro control system 500, digital to analog converter 400 and 600 part.Wherein laser instrument 170, fiber coupler 120 and be attached thereto four optical fiber 121,122,123,124 connect, GRIN Lens 130, quarter-wave plate 140, caesium chamber 150, increase anti-film 160, photodetector 110 and the second photodetector 180 form the physical package 100 of atomic clock of the present invention.
The principle of work of whole system: first micro control system 500 carries out initialization to phase-locked loop 200, phase-locked loop is locked onto in the frequency of atom hyperfine levels transition, and (used herein is half-band width modulation, the frequency that phase-locked loop produces is 4.596GHz), the hyperfine energy level difference of Cs atom is 9.2GHz, micro control system 500 controls to enter the microwave power of physical package 100 by the electric current controlling to enter electrically controlled attenuator 300, makes CPT harmonic peak reach maximum.Judging whether harmonic peak reaches the most direct maximum method is the current signal that extracts physical encapsulation interior lights electric explorer feeds back, after the phase-locked amplifying circuit in periphery, error signal is fed back to micro control system 500, now micro control system 500 pairs of phase-locked loops 200 carry out programming adjustment, the electric current of laser instrument is regulated simultaneously, until system CPT harmonic peak reaches maximum, whole system is locked.
As shown in Figure 2, the phase-locked loop 200 arrived involved in the present invention, mainly comprises temperature compensating crystal oscillator 210, frequency synthesizer 220, third order PLL path filter 230, voltage controlled oscillator 240.Groundwork mode is as follows: temperature compensating crystal oscillator 210 provides benchmark 10MHz frequency, initialized frequency synthesizer 220 is fractional frequency division frequency multiplier, carry out frequency and phase discrimination according to the frequency after voltage controlled oscillator 240 feedback signal frequency division and reference frequency and produce error current, pass through charge pump output error signal again to voltage controlled oscillator, until phase-locked loop system locks onto (4.596GHz) in required frequency.Its loop filter 230 is even more important, and it is by affecting the phase noise of radio frequency output, so the design of loop filter 230 is very important, physical circuit design as shown in Figure 5.
As shown in Figure 3, involved in the present invention to collimating apparatus mainly comprise optical fiber 300, GRIN Lens 310.The function of GRIN Lens 310 obtains required parallel beam, to be re-aggregated in fiber coupler 120 and to output to photodetector 110 from optical fiber 122 simultaneously by from increasing the light that reflects of anti-film 160.
As shown in Figure 4, under the effect of low-intensity magnetic field, Cs atom energy level splitting becomes hyperfine energy level, and for caesium, this energy level difference is 9.2GHz.What the present invention relates to is semi-wave modulated, and the frequency that namely peripheral RF cycle produces equals 4.596GHz.Through ovennodulation, laser is by generation two sidebands, and the difference on the frequency of these two sidebands is just in time 9.2GHz, and now Cs atom will be trapped on hyperfine energy level, no longer will absorb light, and the light intensity being now irradiated to photodetector will occur peak value.For rubidium element, just the energy level difference of hyperfine energy level is different, and the energy level difference of rubidium is 6.8GHz.
Claims (7)
1. an atomic clock, be made up of electronic system and physical package, described physical package comprises laser instrument, conversion light path, quarter wave plate, basic atom bubble air chamber and photodetector, it is characterized in that: four anti-films of optical fiber, GRIN Lens and increasing that described conversion light path comprises four fiber port coupling mechanisms, is connected with fiber coupler, the output terminal of described laser instrument connects the first optical fiber, second Fiber connection GRIN Lens, the 3rd Fiber connection photodetector; The anti-film of described increasing is positioned at the exiting side of basic atom bubble air chamber, emergent light is reflected back basic atom bubble air chamber.
2. atomic clock according to claim 1, it is characterized in that: described laser instrument is for optical gain medium with direct band-gap semicondictor material, inject charge carrier by pn knot and realize population inversion, with Fabry-Perot-type cavity or distribution bragg grating for resonator cavity, carry out the diode laser of stimulated emission light amplification.
3. atomic clock according to claim 1, is characterized in that: described four fiber port coupling mechanisms are 2 × 2 single-mode optical-fibre couplers.
4. atomic clock according to claim 1, is characterized in that: described GRIN Lens is that inner refractive index distributes the lens pillar radially reduced gradually.
5. atomic clock according to claim 1, is characterized in that: the thickness of the anti-film of described increasing equals 1/4th optical maser wavelengths.
6. atomic clock according to claim 1, is characterized in that: be provided with the second photodetector, and described second photodetector connects the 4th optical fiber.
7. the atomic clock according to claim 1 or 6, is characterized in that: described basic atom bubble air chamber is arranged in different individual packages from described laser instrument, photodetector.
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| CN201310252462.8A CN103454902B (en) | 2013-06-24 | 2013-06-24 | A kind of atomic clock |
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| CN201310252462.8A CN103454902B (en) | 2013-06-24 | 2013-06-24 | A kind of atomic clock |
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| CN103454902A CN103454902A (en) | 2013-12-18 |
| CN103454902B true CN103454902B (en) | 2015-12-09 |
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Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106647223A (en) * | 2016-10-13 | 2017-05-10 | 中国电子科技集团公司第二十研究所 | Quick stable real-time adjustment method for atomic clock timing |
| CN106325049A (en) * | 2016-11-08 | 2017-01-11 | 中北大学 | End-coupling nano optical waveguide type dual-optical-path chip-scale atomic clock |
| CN106406074A (en) * | 2016-11-08 | 2017-02-15 | 中北大学 | Perpendicular coupling nanometer optical waveguide dual-optical-path chip atomic clock |
| CN106788426B (en) * | 2016-11-28 | 2019-10-15 | 中国科学院武汉物理与数学研究所 | A kind of CPT atomic frequency standard laser frequency modulation index locking device and method |
| CN106405449A (en) * | 2016-12-05 | 2017-02-15 | 中北大学 | Vertical-coupling nanometer optical waveguide dual-optical-path chip-level magnetometer |
| CN106405450A (en) * | 2016-12-05 | 2017-02-15 | 中北大学 | End-coupling nanometer optical waveguide dual-optical-path chip-level magnetometer |
| CN106877865B (en) * | 2017-01-10 | 2018-08-28 | 清华大学 | Alkali metal gas chamber atomic clock system |
| CN106750469A (en) * | 2017-01-18 | 2017-05-31 | 张文跃 | The process units and production technology of a kind of graphene film coiled material |
| CN110759648A (en) * | 2018-07-25 | 2020-02-07 | 张文跃 | Graphene wire-plated coiled material preparation device and production process |
| CN110760090A (en) * | 2018-07-25 | 2020-02-07 | 张文跃 | Preparation device and production process of PET graphene coated coiled material |
| CN110759330A (en) * | 2018-07-25 | 2020-02-07 | 张文跃 | Preparation device and production process of PET graphene coated coiled material |
| CN111383870B (en) * | 2018-12-28 | 2021-08-13 | 华为技术有限公司 | Ion trap system |
| CN114114884B (en) * | 2021-11-30 | 2023-06-23 | 中国计量科学研究院 | Coherent population trapping cold atomic clock based on grating chip and application method thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102023563A (en) * | 2009-09-23 | 2011-04-20 | 中国计量科学研究院 | Method, apparatus and system for eliminating deposit of atoms on Zeeman cooling window |
| CN102064828A (en) * | 2009-11-12 | 2011-05-18 | 精工爱普生株式会社 | Atomic oscillator |
| CN102684693A (en) * | 2011-03-14 | 2012-09-19 | 精工爱普生株式会社 | Gas cell unit, atomic oscillator and electronic apparatus |
| CN102684694A (en) * | 2011-03-14 | 2012-09-19 | 精工爱普生株式会社 | Optical module for atomic oscillator and atomic oscillator |
| EP2473885B1 (en) * | 2009-09-04 | 2013-05-29 | CSEM Centre Suisse D'electronique Et De Microtechnique SA | Device for atomic clock |
| CN203455615U (en) * | 2013-06-24 | 2014-02-26 | 苏州大学 | Atomic clock |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7379486B2 (en) * | 2005-07-22 | 2008-05-27 | Honeywell International Inc. | Technique for optically pumping alkali-metal atoms using CPT resonances |
| GB0816143D0 (en) * | 2008-09-04 | 2008-10-15 | Univ Glasgow | Frequency reference devices and methods of providing frequency references |
-
2013
- 2013-06-24 CN CN201310252462.8A patent/CN103454902B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2473885B1 (en) * | 2009-09-04 | 2013-05-29 | CSEM Centre Suisse D'electronique Et De Microtechnique SA | Device for atomic clock |
| CN102023563A (en) * | 2009-09-23 | 2011-04-20 | 中国计量科学研究院 | Method, apparatus and system for eliminating deposit of atoms on Zeeman cooling window |
| CN102064828A (en) * | 2009-11-12 | 2011-05-18 | 精工爱普生株式会社 | Atomic oscillator |
| CN102684693A (en) * | 2011-03-14 | 2012-09-19 | 精工爱普生株式会社 | Gas cell unit, atomic oscillator and electronic apparatus |
| CN102684694A (en) * | 2011-03-14 | 2012-09-19 | 精工爱普生株式会社 | Optical module for atomic oscillator and atomic oscillator |
| CN203455615U (en) * | 2013-06-24 | 2014-02-26 | 苏州大学 | Atomic clock |
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