JP2014212429A - Oscillator, rectifier and transceiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oscillator, a rectifier and a transceiver capable of being miniaturized.SOLUTION: An oscillator 100 comprises: an oscillation part 101 having a variable oscillatory frequency by a magnetic field; and conductors 103a, 103b connected to the oscillation part. The oscillation part 101 and conductors 103a, 103b are arranged so that the current flowing into the conductors is higher than that flowing into the oscillation part and a magnetic field generated by the current flowing into the conductors, is applied to the oscillation part.

Description

  The present invention relates to an oscillator, a rectifier, and a transmission / reception device.

  In recent years, microwave oscillation and reception using magnetoresistive elements have been studied. For example, Patent Document 1 discloses that the oscillation frequency can be changed by applying an external magnetic field to a CCP-CPP (Current Confined Path-Current Perpendicular to Plane) oscillation element.

JP 2007-124340 A

  However, in the prior art, the magnetic field necessary for self-excited oscillation and microwave reception has been generated by an external wiring or an external coil or magnet not connected to the magnetoresistive effect element. For example, in Patent Document 1, a magnetic field is applied to a magnetoresistive effect element, which is a self-excited oscillation element, by an external magnet and an external wiring. Therefore, in the prior art, since the number of parts increases and the dimensions of the oscillator and detector increase, it is difficult to reduce the size.

  Therefore, the present invention has been made in view of the above, and an object thereof is to provide an oscillator or a rectifier that can be miniaturized. It is another object of the present invention to provide a transmission / reception apparatus that can be made smaller than before by including such an oscillator and a rectifier.

  In order to achieve the above object, the oscillator according to the first aspect of the present invention is an oscillator including an oscillation unit whose oscillation frequency is variable by a magnetic field, and a conductor connected to the oscillation unit, The conductor is arranged such that a current flowing through the conductor is larger than a current flowing through the oscillating unit, and a magnetic field generated by a current flowing through the conductor is applied to the oscillating unit. This makes it possible to reduce the size of the oscillator.

  The oscillator according to the second aspect of the present invention further includes an oscillation unit whose oscillation frequency is variable by a magnetic field, a current amplification unit that amplifies a current, and a magnetic field application unit that applies a magnetic field to the oscillation unit. The current amplification unit has an input end and an output end, amplifies the current input from the input end and outputs to the output end, the oscillation unit is connected in series to the input end, The magnetic field application unit is connected in series to the output end.

  An oscillator according to a third aspect of the present invention is an oscillator having an oscillation unit whose oscillation frequency is variable by a magnetic field, a current amplification unit that amplifies a current, and a magnetic field application unit that applies a magnetic field to the oscillation unit. The current amplifying unit has an input end and an output end, amplifies the current input from the input end and outputs the amplified current to the output end, and the oscillation unit and the current amplifying unit are connected in parallel. The magnetic field application unit is connected in series to the output end.

  Furthermore, in the oscillator according to the fourth aspect of the present invention, in the oscillator according to any one aspect from the first aspect to the oscillator according to the third aspect, the threshold magnetic field for the oscillation unit to start oscillation is zero. And the magnetic field is larger than the threshold magnetic field.

  Furthermore, in the oscillator according to the fifth aspect of the present invention, in the oscillator according to any one of the first aspect to the third aspect, the oscillation unit includes a magnetoresistive effect element, a Josephson element, or a magnetic resonance filter. It is preferable that the oscillator has a filter.

  In the rectifier according to the sixth aspect of the present invention, the rectifier includes a rectification unit whose rectification frequency is variable by a magnetic field, and a conductor connected to the rectification unit, wherein the rectification unit and the conductor are the conductors. The current flowing through the rectifier is larger than the current flowing through the rectifier, and a magnetic field generated by the current flowing through the conductor is applied to the rectifier.

  The rectifier according to a seventh aspect of the present invention is a rectifier having a rectifier whose rectification frequency is variable by a magnetic field, a current amplifier for amplifying a current, and a magnetic field application unit for applying a magnetic field to the rectifier. The current amplifying unit has an input end and an output end, amplifies the current input from the input end and outputs the amplified current to the output end, the rectifier unit is connected in series to the input end, and the magnetic field The application unit is connected to the output terminal in series.

  A rectifier according to an eighth aspect of the present invention is a rectifier having a rectifier whose oscillation frequency is variable by a magnetic field, a current amplifier for amplifying a current, and a magnetic field application unit for applying a magnetic field to the rectifier. The current amplifying unit has an input end and an output end, amplifies the current input from the input end and outputs to the output end, the rectifier unit and the current amplifying unit are connected in parallel, The magnetic field application unit is connected in series to the output end.

  Furthermore, in the rectifier according to the ninth aspect of the present invention, in the rectifier according to any one aspect from the sixth aspect to the rectifier according to the eighth aspect, the threshold magnetic field for causing the rectifier to exhibit a rectifying action is zero. And the magnetic field is larger than the threshold magnetic field.

  Furthermore, in the rectifier according to the tenth aspect of the present invention, in the rectifier according to any one aspect from the sixth aspect to the rectifier according to the eighth aspect, the rectifier is a magnetoresistive effect element or a Josephson element. It is preferable to be characterized by this.

  The transceiver device according to the eleventh aspect of the present invention includes the oscillator according to the first aspect and the rectifier according to the sixth aspect, wherein the conductor of the oscillator and the conductor of the rectifier are electromagnetically connected. By combining, wireless communication or wireless power transmission is performed.

  Furthermore, the transmitter / receiver according to the twelfth aspect of the present invention includes the oscillator according to the second or third aspect and the rectifier according to the seventh or eighth aspect, and the magnetic field applying unit of the oscillator And the magnetic field application unit of the rectifier are electromagnetically coupled to perform wireless communication or wireless power transmission.

  The present invention has been made in view of the above problems, and can provide an oscillator or a rectifier that can be miniaturized. In addition, by including such an oscillator and a rectifier, it is possible to provide a transmission / reception device that can be made smaller than before.

1 is a schematic diagram of an oscillator according to Embodiment 1 of the present invention. It is a figure which shows the structural example of the magnetoresistive effect element which concerns on embodiment of this invention. It is a figure which shows the structural example of the oscillator with a filter which concerns on embodiment of this invention. It is a figure which shows the peripheral circuit of the oscillator which concerns on Embodiment 1 of this invention. It is a schematic diagram of the oscillator according to Embodiment 2 of the present invention. It is a schematic diagram of the oscillator concerning Embodiment 3 of the present invention. It is a schematic diagram of the oscillator which concerns on Embodiment 4 of this invention. FIG. 10 is a schematic diagram of an oscillator related to embodiment 5 of this invention. It is a schematic diagram of the oscillator concerning Embodiment 6 of the present invention. It is a schematic diagram of the rectifier which concerns on Embodiment 7 of this invention. It is a figure which shows the peripheral circuit of the rectifier which concerns on Embodiment 6 of this invention. It is a circuit diagram of the transmission apparatus which concerns on Embodiment 10 of this invention. It is a figure which shows the transmission / reception apparatus in Embodiment 13 of this invention.

  Hereinafter, an example of an embodiment for carrying out the present invention will be described with reference to the drawings. The following description exemplifies a part of the embodiments of the present invention, and the present invention is not limited to these embodiments, so long as the form has the technical idea of the present invention. It is included in the scope of the present invention. Each configuration in each embodiment, a combination thereof, and the like are examples, and the addition, omission, replacement, and other changes of the configuration can be made without departing from the spirit of the present invention.

(Embodiment 1)
FIG. 1 is a schematic diagram of an oscillator according to the first embodiment. The oscillator 100 according to the first embodiment includes an oscillating unit 101, a conductor 103a and a conductor 103b connected in series to the oscillating unit 101, and a current amplifying unit 104 that is a current amplifying unit. The current amplifying unit 104 has an input end and an output end, amplifies the current input from the input end, and outputs the amplified current to the output end. The oscillation unit 101 is connected in series to the input end of the current amplification unit 104, and the conductor 103 b is connected in series to the output end of the current amplification unit 104.

When a DC current I to the oscillation unit 101, current amplifier 104 generates an amplified current _{I A.} Conductors 103b by the amplified current _{I A} flows, to generate a first magnetic field H. The conductor 103b is disposed so that the first magnetic field H is larger than the threshold magnetic field for the oscillation unit 101 to oscillate. Here, the threshold magnetic field is the minimum magnetic field required for the oscillation unit 101 to oscillate when the direct current I is supplied to the oscillation unit 101. The oscillation unit 101 oscillates when the direct current I and the first magnetic field H are applied.

  In order to cause the oscillation unit 101 to oscillate using the oscillation unit having a threshold magnetic field greater than zero, it is necessary to apply a magnetic field greater than zero together with the direct current I to the oscillation unit 101. When the oscillating unit 101 that does not oscillate only by the direct current I is used, a magnetic field greater than the geomagnetism is applied. Incidentally, the geomagnetism here indicates the earth magnetism acting on the oscillator, and for example, the earth magnetism on the earth's surface is 37 A / m as a guide.

  The conductor 103b can be disposed in the immediate vicinity of the oscillation unit 101, and a strong magnetic field equal to or higher than the threshold value can be applied to the oscillation unit 101. Therefore, the entire oscillator can be reduced in size.

  The oscillator 100 is configured such that the current flowing through the conductor 103b is larger than the current flowing through the oscillation unit 101. Therefore, since a large current does not flow through the oscillation unit 101, the oscillation unit 101 can be protected from an overcurrent.

  A transistor, a commercially available chip-shaped amplifier, an amplifier circuit, or the like can be used as the current amplifying unit serving as a current amplifying unit, but is not limited thereto.

  As the oscillation unit 101, for example, a magnetoresistive effect element, an oscillator with a filter including an oscillation circuit and a filter using magnetic resonance, a Josephson element, or a Zeeman laser can be used.

  FIG. 2 shows a configuration example of the magnetoresistive effect element. The magnetoresistive effect element 205 includes a pinned layer 206a that is a magnetic layer, a free layer 206b that is a magnetic layer, and a spacer layer 207 disposed therebetween. Here, the magnetization direction of the pinned layer 206a is fixed, and the arrow 209a indicates the pinned direction of the magnetization of the pinned layer 206a. The magnetization direction of the free layer 206b is in the direction of the effective magnetic field before the current is applied, and the arrow 209b indicates the direction of the effective magnetic field. The effective magnetic field is the sum of an anisotropic magnetic field, an exchange magnetic field, an external magnetic field, and a demagnetizing field generated in the free layer 206b. In FIG. 2, the magnetization direction of the pinned layer 206a and the effective magnetic field direction of the free layer 206b are opposite to each other, but the directions are not limited to this.

  The magnetoresistive effect element 205 is not particularly limited. For example, a GMR element, a TMR element, or a magnetoresistive effect element in which a current confinement path exists in the insulating layer of the spacer layer 207 can be used.

  When a GMR element is used for the magnetoresistive effect element 205, the spacer layer 207 can be made of a nonmagnetic metal such as copper, for example. As a material of the free layer 206b and the pinned layer 206a of the GMR element, for example, a magnetic metal such as cobalt, iron, nickel, and chromium and an alloy thereof, or an alloy in which boron is mixed into the magnetic alloy can be used. In order to fix the magnetization of the pinned layer 206a, exchange coupling with an antiferromagnetic layer made of an alloy such as iridium, iron, platinum, manganese, or a magnetic metal multilayer film (for example, a multilayer film of cobalt iron-ruthenium-cobalt iron) is used. Antiferromagnetic coupling can be used. The thickness of each layer is preferably about 0.1 to 50 nm. Since the spacer layer 207 is made of metal, the GMR element has a resistance value lower than that of other magnetoresistive elements. For this reason, when connecting the magnetoresistive effect element 205 to a low impedance circuit, it is preferable from the viewpoint of impedance matching.

  When a TMR element is used as the magnetoresistive effect element 205, the spacer layer 207 can be an insulating layer of alumina or magnesium oxide (MgO), for example. As a material of the free layer 206b and the pinned layer 206a of the TMR element, for example, a magnetic metal such as cobalt, iron, nickel, and chromium and an alloy thereof, or an alloy mixed with boron as a magnetic alloy can be used. In order to fix the magnetization of the pinned layer 206a, exchange coupling with an antiferromagnetic layer made of an alloy such as iridium, iron, platinum, manganese, or a magnetic metal multilayer film (for example, a multilayer film of cobalt iron-ruthenium-cobalt iron) is used. Antiferromagnetic coupling can be used. The thickness of each layer is preferably about 0.1 to 50 nm. Since the spacer layer 207 is made of an insulating layer, the TMR element has a higher resistance value than other magnetoresistive elements. For this reason, it is preferable from the viewpoint of impedance matching when the magnetoresistive effect element 205 is connected to a high impedance circuit.

Further, when a magnetoresistive effect element having a current confinement path in the insulating layer of the spacer layer 207 is used as the magnetoresistive effect element 205, the insulating layer of the spacer layer 207 is made of Al ₂ O ₃ or the like. For the current confinement path of the spacer layer 207, for example, a nonmagnetic metal such as copper, a magnetic metal such as cobalt, iron, nickel, or chromium and an alloy thereof, or a magnetic metal obtained by mixing boron into the magnetic alloy can be used. For the magnetization free layer and the magnetization fixed layer of the magnetoresistive effect element 205, for example, a magnetic metal such as cobalt, iron, nickel, and chromium and an alloy thereof, or an alloy in which boron is mixed into the magnetic alloy can be used. In order to fix the magnetization of the pinned layer 206a, exchange coupling with an antiferromagnetic layer made of an alloy such as iridium, iron, platinum, manganese, or a magnetic metal multilayer film (for example, a multilayer film of cobalt iron-ruthenium-cobalt iron) is used. Antiferromagnetic coupling can be used. The thickness of each layer is preferably about 0.1 to 50 nm. The magnetoresistive effect element 205 has a current confinement path, and the current density can be increased by the current confinement path. For this reason, the input current to the element can be reduced as compared with other magnetoresistive elements. By using the magnetoresistive effect element 205 for the oscillation unit 101, a circuit with reduced power consumption can be obtained.

  The self-excited oscillation of the magnetoresistive effect element 205 according to this embodiment will be described. Here, self-excited oscillation is a phenomenon in which electrical vibration is induced by a non-vibrating direct current. When a direct current I is passed through the magnetoresistive effect element 205, conduction electrons 208 flow in the opposite direction of the direct current I, that is, from the pinned layer 206a to the free layer 206b via the spacer layer 207. In the pinned layer 206a magnetized in the direction of the arrow 209a, the spin of the conduction electron 208 is polarized in the direction of the arrow 209a. An arrow 209 c represents the spin direction of the conduction electron 208. The spin-polarized electrons 208 flow into the free layer 206b through the spacer layer 207, thereby transferring magnetization and angular momentum of the free layer 206b. As a result, the action of tilting the magnetization direction of the free layer 206b from the direction of the arrow 209b indicating the direction of the effective magnetic field works. On the other hand, a damping action is performed to stabilize the magnetization direction of the free layer 206b in the direction of the arrow 209b indicating the direction of the effective magnetic field. Therefore, these two effects are balanced, and the magnetization direction of the free layer precesses around the direction of the effective magnetic field. This precession is expressed as a movement of an arrow 209d indicating the magnetization direction of the free layer around an arrow 209b indicating the direction of the effective magnetic field, and a locus of the precession indicated by the arrow 209d is indicated by a one-dot chain line 209e. Since the magnetization direction of the free layer changes at a high frequency with respect to the magnetization direction of the pinned layer, the resistance value also varies due to the magnetoresistive effect in which the resistance changes depending on the relative angle between the magnetization direction of the free layer and the magnetization direction of the pinned layer Changes at high frequencies. Since the resistance value changes at a high frequency with respect to the direct current I, a voltage that oscillates at a high frequency of about 100 MHz to 1 THz is generated. The direction of the effective magnetic field not only has an angle of 180 degrees opposite to the magnetization direction of the pinned layer 206a, but also an angle such as 0 degrees, 45 degrees, 90 degrees, or 135 degrees that is the same direction. Can have.

  The applied magnetic field and the oscillation frequency are approximately proportional. Therefore, it is desirable that the external magnetic field is large in order to generate high-frequency oscillation.

  Further, the oscillator 101 can use an oscillator with a filter that includes an oscillation circuit and a filter using magnetic resonance. FIG. 3 is a diagram showing a configuration example of an oscillator with a filter. The filter-equipped oscillator 300 includes an oscillation circuit 301, a filter 302 using magnetic resonance, and a conductor 103. The conductor 103 includes a portion that supplies a current to the oscillator with filter 300, a portion from which current flows out from the oscillator 300 with filter, and a portion that connects the oscillation circuit 301 and the filter 302. In the oscillator with filter 300, it is desirable to dispose the conductor 103 and the filter 302 using magnetic resonance so that a magnetic field generating current can be efficiently applied to the filter 302 using magnetic resonance.

For example, a YIG oscillator can be used as the filtered oscillator 300 using a filter using magnetic resonance. YIG is an abbreviation for Yttrium Iron Garnet / Y ₃ Fe ₂ (FeO ₄ ) ₃ . The YIG oscillator is composed of an oscillation circuit and YIG. YIG is preferably spherical. A sphere made of single crystal ferrite of YIG exhibits a sharp magnetic resonance when a magnetic field is applied, and thus functions as a filter that passes a signal of that frequency. Oscillation occurs when a current is passed through the oscillation circuit, and the oscillation is output as a sharp peak spectrum by passing the oscillation signal through YIG functioning as a filter.

  The frequency of the signal that YIG passes is determined by the magnetic resonance frequency that is approximately proportional to the magnitude of the applied magnetic field. Accordingly, a large external magnetic field is required to oscillate at a high frequency even in the oscillator 300 with a filter using a filter using magnetic resonance.

  An oscillation element using an AC Josephson effect can be used for the oscillation unit 101. The AC Josephson effect is an effect in which an AC current flows through a junction when a DC current of a threshold value or more is supplied to a Josephson junction connecting two superconductors. Furthermore, it is known that the frequency of alternating current can be changed by applying an external magnetic field to the Josephson junction. Therefore, an oscillating element using the AC Josephson effect can be used as an oscillating portion whose frequency is variable by an external magnetic field.

  A Zeeman laser can also be used for the oscillation unit 101. The Zeeman laser is a laser that uses the Zeeman effect in which the energy level of an atom is split by a magnetic field. When a magnetic field and a current are applied to a laser oscillation unit, two polarized components having different frequencies are oscillated. Furthermore, it is known that the oscillation frequency can be changed by a magnetic field. Therefore, the Zeeman laser can be used as an oscillation unit whose frequency is variable by an external magnetic field.

  FIG. 4 is a diagram illustrating an example of a peripheral circuit for using the oscillator 100 according to the first embodiment. The peripheral circuit 400 includes a direct current source 402, a load 404, an inductor La, and a capacitor Ca. The inductor La can prevent the high frequency output generated by the oscillator 100 from flowing into the direct current source 402, and the capacitor Ca can prevent the direct current from flowing into the load 404.

  When a direct current is supplied from the direct current source 402 to the oscillator 100, the oscillator 100 outputs a high frequency. The high-frequency signal mainly passes through the capacitor Ca having a smaller impedance than the inductor La, and is detected by the load 404.

In the following description of the embodiments, the peripheral circuit 400 is omitted.

(Embodiment 2)
In the second embodiment, an oscillator provided with a magnetic field applying unit that applies a stronger magnetic field to the oscillating unit as compared with the first embodiment will be described.

  FIG. 5 is a schematic diagram of an oscillator according to the second embodiment. An oscillator 500 according to the second embodiment includes an oscillating unit 101, conductors 103 a and 103 b connected in series to the oscillating unit 101, and a current amplifying unit 104. The conductor 103b has a loop portion that is a magnetic field application portion, and the loop portion is represented by an inductor 502. The oscillation unit 101 is connected in series to the input end of the current amplification unit 104, and the loop unit is connected in series to the output end of the current amplification unit 104.

When a DC current I to the oscillation unit 101, current amplifier 104 generates an amplified current _{I A.} Loop portion by amplifying current I _A flows, to generate a first magnetic field H. The loop part is arranged so that the first magnetic field H is larger than a threshold magnetic field for the oscillation part 101 to oscillate.

  In the second embodiment, a stronger magnetic field can be applied to the oscillating unit 101 by configuring a loop unit that is a magnetic field applying unit. Therefore, Embodiment 2 is a more preferable form when it is desired to obtain higher-frequency oscillation while protecting the element from current.

  Furthermore, the loop part can also be used as an antenna that emits the electric power oscillated by the oscillation part 101 as an electromagnetic field. Therefore, when the electromagnetic field is emitted from the oscillator to the outside, it is not necessary to newly provide an antenna, and the entire oscillator can be reduced in size. Here, the term “antenna” means not only an antenna for transmitting an electromagnetic wave to a distance sufficiently larger than a wavelength, but also an antenna or a resonator for transmitting an electromagnetic field to a distance similar to or smaller than the wavelength.

(Embodiment 3)
FIG. 6 is a schematic diagram according to the third embodiment. An oscillator 600 according to the third embodiment includes an oscillating unit 101, conductors 103 a and 103 b connected in series to the oscillating unit 101, a magnet 601, and a current amplifying unit 104. The oscillation unit 101 is connected in series to the input end of the current amplification unit 104, and the conductor 103 b is connected in series to the output end of the current amplification unit 104.

In the third embodiment, the number of the magnets 102 is two, but it is sufficient that only one magnet 102 can be used as the magnetic field applied to the oscillation unit 101. However, it is preferable to arrange two magnets 601 rather than one because the bias of the magnetic field applied to the oscillation unit 101 is reduced. The magnet 601 and the second magnetic field, are arranged to apply a magnetic field H _m to the oscillation portion 101. The magnet may be a hard bias film formed of a magnetic metal such as cobalt, iron, nickel, or chromium and an alloy thereof, or an alloy in which boron is mixed into the magnetic alloy.

When a DC current I to the oscillation unit 101, current amplifier 104 generates an amplified current _{I A.} Conductor 103b generates a first magnetic field H in the position of the oscillator 101 by amplifying the current _{I A} flows. Conductor 103b is disposed so that the resultant magnetic field and the first magnetic field H and the second magnetic field H _m is greater than the threshold magnetic field.

  Further, if the applied magnetic field intensity is adjusted by changing the position of the magnet 601, the oscillation frequency of the oscillation unit 101 can be changed.

  The magnetic field applying means for applying the second magnetic field is not limited to a magnet, and for example, an external wiring, an external coil, or an electromagnet can be used.

Embodiment 3, by a synthetic magnetic field of the first magnetic field H and the second magnetic field H _m, can apply a relatively strong magnetic field to the oscillation portion 101. Therefore, this is a more preferable embodiment when it is desired to obtain oscillation at a higher frequency.

(Embodiment 4)
In the fourth embodiment, the configurations of the second embodiment and the third embodiment can be used together, a stronger magnetic field can be applied to the oscillating unit 101, and higher-frequency oscillation can be obtained.

  FIG. 7 is a schematic diagram of an oscillator according to the fourth embodiment. The oscillator 700 according to the fourth embodiment includes an oscillating unit 101, conductors 103 a and 103 b connected in series to the oscillating unit 101, a magnet 601, and a current amplifying unit 104. The conductor 103b has a loop portion that is a magnetic field application portion, and the loop portion is represented by an inductor 502. The oscillation unit 101 is connected in series to the input end of the current amplification unit 104, and the loop unit is connected in series to the output end of the current amplification unit 104.

When a DC current I to the oscillation unit 101, current amplifier 104 generates an amplified current _{I A.} The loop unit, which is a magnetic field application unit, generates the first magnetic field H at the position of the oscillation unit 101 when the amplified current I _A flows. Loop portion is arranged so that the resultant magnetic field and the first magnetic field H and the second magnetic field H _m is greater than the threshold magnetic field.

Embodiment 4 includes a first magnetic field H loop portion is a magnetic field applying unit generates the amplified current, by a synthetic magnetic field of the second magnetic field H _m by the external magnetic field applying mechanism, a relatively strong magnetic field oscillating unit 101 can be applied. Therefore, this is a more preferable embodiment when it is desired to obtain oscillation at a higher frequency.

(Embodiment 5)
The arrangement of the current amplifying means is not limited to the arrangement in which the oscillation unit 101 and the current amplifying means are in series as shown in the first to fourth embodiments. Any structure may be used as long as the current flowing through the conductor 103b is larger than the current flowing through the oscillation unit 101. In the fifth embodiment, the oscillating unit 101 and the current amplifying unit are arranged in parallel.

  FIG. 8 is a schematic diagram of an oscillator according to the fifth embodiment. An oscillator 800 according to the fifth embodiment includes an oscillating unit 101, and a conductor 103a and a conductor 103b connected in series to the oscillating unit 101. Furthermore, the oscillator 800 includes a current amplifying unit 104 in parallel with the oscillating unit 101. The input terminal of the oscillation unit 101 is connected to the input terminal of the current amplification unit 104, and the output terminal of the oscillation unit 101 is connected to the output terminal of the current amplification unit 104.

When a direct current I is passed through the oscillator 800, the current amplifying unit 104 generates an amplified current. Conductors 103b, by the current I _A plus amplified current as the current passing through the oscillation portion 101 flows to generate a first magnetic field H. The conductor 103b is disposed so that the first magnetic field H is larger than the threshold magnetic field for the oscillation unit 101 to oscillate.

  In the fifth embodiment, since the direct current I is shunted to the oscillation unit 101 and the current amplification unit 104, the current flowing through the oscillation unit 101 can be further reduced. This is a more preferable mode when the oscillation unit 101 has a small withstand current and it is desired to obtain high-frequency oscillation while protecting the element from current.

  In the fifth embodiment, the form in which the input terminal of the oscillation unit 101 and the input terminal of the current amplification unit 104 are connected has been described. However, the configuration in which the input terminal of the current amplification unit 104 is connected to an external current supply source is described. It can also be used. Even in this configuration, the magnitude of the current flowing through the conductor 103b can be made larger than the current flowing through the oscillation unit 101.

(Embodiment 6)
In the fifth embodiment, the arrangement in which the oscillation unit 101 and the current amplification unit 104 are arranged in parallel has been described. In the sixth embodiment, the magnetic field application unit and the current amplification unit 104 connected in series are connected in parallel to the oscillation unit 101. An oscillator connected and configured is shown.

  FIG. 9 is a schematic diagram of an oscillator according to the sixth embodiment. An oscillator 800b according to the sixth embodiment includes an oscillating unit 101, conductors 103a and 103b connected in series to the oscillating unit 101, a current amplifying unit 104, and a magnetic field applying unit. The magnetic field application unit includes a loop unit and is expressed by an inductor 502. The current amplification unit 104 and the loop unit are connected in series, and the series connection is connected to the oscillation unit 101 in parallel. The input terminal of the current amplification unit 104 is connected to the input terminal of the oscillation unit 101, and the output terminal of the current amplification unit 104 is connected in series to the loop unit.

When a DC current I to the oscillator 800b, current amplifier 104 generates an amplified current _{I A.} The loop unit, which is a magnetic field application unit, generates the first magnetic field H when the amplified current I _A flows. The loop part is arranged so that the first magnetic field H is larger than a threshold magnetic field for the oscillation part 101 to oscillate.

  In the sixth embodiment, since the direct current I is divided into the oscillation unit 101 and the current amplification unit 104, the current flowing through the oscillation unit 101 can be further reduced. This is a more preferable mode when the oscillation unit 101 has a small withstand current and it is desired to obtain high-frequency oscillation while protecting the element from current.

  In the sixth embodiment, the form in which the input terminal of the oscillation unit 101 and the input terminal of the current amplification unit 104 are connected has been described. However, the configuration in which the input terminal of the current amplification unit 104 is connected to an external current supply source is described. It can also be used. Even in this configuration, the magnitude of the current flowing through the conductor 103b can be made larger than the current flowing through the oscillation unit 101.

  The oscillator of the present invention is not limited to the above-described embodiment. For example, the magnetic field applied to the oscillating unit 101 may be smaller than the threshold magnetic field, and may be oscillated by applying another magnetic field. Furthermore, Embodiments 1 to 6 may be used to cause the oscillation unit 101 having a threshold magnetic field of 0 [A / m] to oscillate at a desired frequency. Furthermore, although the form which uses a loop part as a magnetic field application part was demonstrated, a magnetic field application part is not restricted to a loop part. For example, the magnetic field application unit may be configured in a semicircular winding shape that does not lead to the complete formation of the loop, or in other shapes such as a linear shape or a curved shape.

(Embodiment 7)
In Embodiment 7, in the oscillator 100 of the first embodiment, the oscillation unit 101 replaces a rectification part, by further into AC current I _AC and DC current I, shows a rectifier for converting alternating current into direct current. In particular, in the seventh embodiment, the rectifying unit is the magnetoresistive effect element 205.

FIG. 10 is a schematic diagram of a rectifier 900 according to the seventh embodiment. In the rectifier 900 according to the seventh embodiment, the DC current I according to the first embodiment is changed to the AC current _IAC, and the magnetoresistive effect element 205 is used as a rectifying unit replaced with the oscillation unit 101. Upon application of an alternating current _{I AC} through the conductors 103 to the magnetoresistive element 205, the conductor 103b generates a magnetic field _{H AC} by amplified AC current _{I AC-A.} Conductor 103b is disposed so as the magnetic field _{H AC} is applied to the magnetoresistive effect element 205. The magnetic field _{H AC} is, if exceeding the threshold magnetic field necessary to spin torque FMR (Ferromagnetic Resonance) effect to be described later occurs, the magnetoresistive element 205 converts the alternating current to direct current. That is, the rectifier 900 of the seventh embodiment is a rectifier. Here, the threshold magnetic field is the magnitude of the minimum magnetic field required for the magnetoresistive element 205 to exhibit the spin torque FMR effect when an alternating current is supplied to the magnetoresistive element 205.

  Here, the spin torque FMR effect will be described. Consider the case where an alternating current is applied to the magnetoresistive effect element 205 in FIG. 2 in the direction perpendicular to the plane of each layer. When electrons 208 are injected from the pinned layer 206a into the free layer 206b in a half cycle of alternating current, the magnetization direction of the free layer 206b rotates so that the magnetizations of the free layer 206b and the pinned layer 206a are parallel to each other. The resistance value of the element 205 decreases. Conversely, in the half cycle in which electrons 208 are injected from the free layer 206b to the pinned layer 206a, the magnetization direction of the free layer rotates so that the magnetization directions of the free layer 206b and the pinned layer 206a are antiparallel to each other, and the resistance value is Go up. This resistance change phenomenon occurs alternately by the alternating current, and a direct current voltage component is generated along with the oscillating voltage. That is, it shows a rectifying action for converting alternating current into direct current. This is called the spin torque FMR effect. Since the frequency at which the spin torque FMR effect occurs, that is, the rectification frequency depends on the applied magnetic field, it is necessary to apply a sufficient magnetic field to generate the spin torque FMR effect at a desired frequency.

The conductor 103b can be disposed in the immediate vicinity of the magnetoresistive effect element 205 which is a rectifying unit. The conductor 103b can apply a strong magnetic field equal to or higher than the threshold to the rectifying unit by the amplified alternating current I _AC-A . Therefore, the entire rectifier can be reduced in size.

  The rectifier 900 is configured such that the current flowing through the conductor 103b is larger than the current flowing through the magnetoresistive effect element 205 as a rectifying unit. Therefore, since a large current does not flow through the rectifying unit, the rectifying unit can be protected from overcurrent.

  In addition to the magnetoresistive effect element, for example, a Josephson element can be used for the rectifying unit.

  A transistor, a commercially available chip-shaped amplifier, an amplifier circuit, or the like can be used as the current amplifying unit serving as a current amplifying unit, but is not limited thereto.

  FIG. 11 is a diagram illustrating an example of a peripheral circuit for using the rectifier 900 according to the seventh embodiment. The peripheral circuit 1000 includes an alternating current source 1002, a load 1004, an inductor La, and a capacitor Ca. The inductor La can prevent the alternating current from flowing into the load 1004, and the capacitor Ca can prevent the direct current generated by the spin torque FMR effect from flowing into the alternating current source 1002.

The alternating current I _AC from the alternating current source 1002 passes through the capacitor Ca having a small impedance, but hardly passes through the inductor La having a large impedance. Therefore, the alternating current I _AC is efficiently supplied to the rectifier 900. The rectifier 900 converts the alternating current _IAC into a direct current, and the direct current output is detected by the load 1004.

  In the following description of the embodiment, the peripheral circuit 1000 is omitted.

(Embodiment 8)
In the eighth embodiment, the magnetoresistive effect element 205 is used as the rectifying unit replacing the oscillating unit 101 in the second to sixth embodiments, and the direct current I is changed to the alternating current _IAC , thereby generating the amplified current _IAC-A. The magnetic field _HAC to be applied is efficiently applied to the magnetoresistive effect element 205. In the eighth embodiment, the alternating current I _AC and the magnetic field _HAC are applied to the magnetoresistive effect element 205, so that the magnetoresistive effect element 205 rectifies alternating current to direct current by the spin torque FMR effect, and thus becomes a rectifier.

  Furthermore, the loop part which is a magnetic field application part can be used also as an antenna which receives the electromagnetic field from the outside and supplies electric power to a rectifier. Therefore, when an electromagnetic field is supplied to the rectifier from the outside, it is not necessary to newly provide an antenna, and the rectifier can be miniaturized. Here, the term “antenna” means not only an antenna for receiving an electromagnetic wave coming from a distance sufficiently larger than a wavelength, but also an antenna or a resonator for receiving an electromagnetic field from a distance similar to or smaller than the wavelength.

  The rectifier of the present invention is not limited to the seventh and eighth embodiments. For example, the magnetic field applied to the magnetoresistive effect element 205 is smaller than the threshold magnetic field for causing the spin torque FMR effect, and another magnetic field is used. The intensity at which the spin torque FMR effect is manifested by application may be used. Further, the present invention may be used to cause the spin torque FMR effect at a desired frequency for the magnetoresistive element 205 having a threshold magnetic field of 0 [A / m]. Furthermore, also in the rectifier, the magnetic field application unit is not limited to the loop unit. For example, the magnetic field application unit may be formed in a semicircular winding shape that does not lead to complete formation of the loop, or in other shapes such as a linear shape.

(Embodiment 9)
In the ninth embodiment, in the rectifier described in the seventh or eighth embodiment, a magnetic field generated by the signal current is efficiently applied to the magnetoresistive effect element 205 by changing the alternating current _IAC to a signal current. In the ninth embodiment, a signal current and a magnetic field generated by the signal current are applied to the magnetoresistive effect element 205, so that the spin torque FMR effect is generated, and the signal current is rectified and received, so that it becomes a receiver. .

(Embodiment 10)
In the tenth embodiment, in order to wirelessly transmit the output of the oscillating unit, a means for transmitting the output of the oscillating unit by electromagnetic coupling is provided in an electric circuit that is galvanically insulated from the oscillator. Electromagnetic coupling includes inductive coupling by electromagnetic induction, coupling by capacitance, coupling by electromagnetic resonance, coupling by electromagnetic waves, and the like. In the tenth embodiment, an embodiment using inductive coupling will be described.

  FIG. 12 is a circuit diagram of a transmission device 1100 according to the tenth embodiment. The transmission device 1100 includes a first electric circuit 1101 and a second electric circuit 1102. The first electric circuit 1101 includes the oscillator 500 and the electric circuit 1105 of the second embodiment. The loop portion of the oscillator 500 is expressed by a first inductor 502. Here, for simplification of the drawing, the current amplifying unit 104 of the second embodiment is omitted and not shown. The second electric circuit 1102 includes a conductor 1107 and an electric circuit 1106. Although not shown, the electric circuit 1106 includes an antenna that transmits a signal to the outside of the transmission device 1100. The conductor 1107 has a loop portion and is represented by a second inductor 1104. The oscillator 500 and the second electric circuit 1102 are galvanically isolated. The first inductor 502 and the second inductor 1104 are galvanically isolated but are inductively coupled.

  When the oscillator 500 oscillates, a time-varying current flows through the first inductor 502, and a signal from the electric circuit 1101 is transmitted to the electric circuit 1102 via the second inductor 1104 by inductive coupling.

If impedance matching is considered in the inductive coupling portion, reflection is reduced in the inductive coupling portion, so that signal transmission is performed more efficiently. The impedance of the first electric circuit 1101 is Z1, and the impedance of the second electric circuit 1102 is Z2. In order to match the impedances of the two electric circuits, the number of turns of the first inductor 502 and the second inductor 1104 is adjusted. This technique is known as an impedance matching technique using a transformer. If the number of turns N1 of the first inductor 502 and the number of turns N2 of the second inductor 1104 are determined so as to satisfy the following formula (2), the impedances of the first electric circuit 1101 and the second electric circuit 1102 are determined. Is consistent.
(N1 / N2) ² = Z1 / Z2 (2)

  The magnitude of the magnetic field applied to the oscillation unit 101 can be adjusted by the number of turns of the inductor. When the number of turns N1 of the first inductor 502 is adjusted for impedance matching, the magnetic field applied to the oscillation unit 101 is changed. Therefore, it is desirable to adjust the number of turns N2 of the second inductor 1104.

  The first inductor 502 and the second inductor 1104 are, for example, a configuration in which an iron core or other magnet is disposed in the shaft portion of the loop portion, or a configuration in which the first inductor 502 and the second inductor 1104 are provided in the toroidal core. It may be. The configuration is a preferable form when it is desired to strengthen inductive coupling.

  Although the oscillator 500 of the second embodiment has been described as an example of the oscillator, the oscillator is not particularly limited, and for example, an oscillator in another embodiment can be used.

(Embodiment 11)
In the eleventh embodiment, in the oscillator 500 of the tenth embodiment, the oscillating unit 101 is replaced with a rectifying unit using the magnetoresistive effect element 205. Embodiment 11, when an alternating current is supplied I _AC to the conductor 1107, magnetic field and current first inductor 502 induced coupling occurs is, since it is applied to the magnetoresistive element 205, the magnetoresistive element 205 is spin It becomes a rectifier that generates a DC voltage from an AC current by the torque FMR effect.

The configuration of the rectifying device is not limited to the configuration in which the oscillating unit 101 in the oscillator 500 according to the tenth embodiment is replaced with a rectifying unit using the magnetoresistive effect element 205. In the eleventh embodiment, the oscillator 500 of the second embodiment is used, but any of the oscillators in the first to sixth embodiments may be used. The rectifier can also be configured by replacing the oscillator 101 of the oscillator with the magnetoresistive element 205 which is a rectifier. In this configuration, when an alternating current I _{AC is} passed through the conductor 1107, a magnetic field and current generated by electromagnetic coupling are applied to the magnetoresistive effect element 205, so that the magnetoresistive effect element 205 is alternating current due to the spin torque FMR effect. The rectifier generates a DC voltage from the current. Here, the electromagnetic coupling means inductive coupling by electromagnetic induction, coupling by capacitance, coupling by electromagnetic resonance, coupling by electromagnetic waves, etc., but is not limited thereto.

Embodiment 12
In the twelfth embodiment, when a signal current is passed through the conductor 1107 in the rectifier described in the eleventh embodiment, the magnetic field and current generated in the oscillator by electromagnetic coupling are applied to the magnetoresistive effect element 205. In the twelfth embodiment, since the magnetoresistive effect element 205 rectifies and receives a signal current by a spin torque FMR effect, it becomes a receiving device. Here, the electromagnetic coupling means inductive coupling by electromagnetic induction, coupling by capacitance, coupling by electromagnetic resonance, coupling by electromagnetic waves, etc., but is not limited thereto.

(Embodiment 13)
Embodiment 13 in which a conductor that applies a magnetic field to the oscillation unit 101 is used as a communication antenna will be described.

  FIG. 13 is a diagram illustrating a transmission / reception apparatus according to the thirteenth embodiment. The transmission / reception device 1200 includes an oscillator 1201a and a receiver 1201b. The oscillator 1201a uses the second embodiment as an example. That is, the oscillator 1201a includes the oscillating unit 101, and the conductor 103a and the conductor 103b that are connected in series to the oscillating unit 101 and input a transmission signal, and the conductor 103b includes the loop unit 1202a. Here, for simplification of the figure, the current amplifying unit is omitted and not shown. The receiver 1201b includes a conductor 1202b having means for receiving an electromagnetic field generated by the loop unit 1202a, and a conversion unit 1203 for converting the electromagnetic field received by the conductor 1202b into a received signal.

  The operation of the transmission / reception device 1200 will be described. In the description here, NRZ (Non-Return-to-Zero) is used as the communication encoding method. NRZ is an encoding method in which the voltage is not zero when the signal is “1” and the voltage is zero when the signal is “0”. However, the encoding method that can be used in the present invention is not limited to this.

  When the signal value is “1”, a current flows through the loop unit 1202 a and the oscillation unit 101 for a time interval of “1”, and the loop unit 1202 a generates a magnetic field H. The oscillation unit 101 oscillates at a desired frequency when a current necessary for oscillation and a magnetic field H are applied. When the oscillated voltage is applied to the loop unit 1202a, the loop unit 1202a is superimposed on the magnetic field H to generate the electromagnetic field EM. The electromagnetic field EM is received by the conductor 1202b of the receiver 1201b. The received electromagnetic field is converted into a received signal by the converter 1203, and the signal value “1” is transmitted.

  When the signal value is “0”, no current flows through the oscillating unit 101 and no magnetic field is generated, so that the electromagnetic field is not transmitted to the receiver 1201b. That is, the signal value “0” is transmitted.

  In this embodiment, the loop unit 1202a provided for applying a magnetic field to the oscillation unit 101 is also used as an antenna used for wireless transmission. Therefore, it is not necessary to newly provide an antenna for wireless transmission, and the transmission / reception apparatus can be downsized.

  Further, when the signal value is “0”, no current flows through the loop portion 1202a, so that an electromagnetic field unnecessary for communication is not generated. That is, this embodiment can also be expected to save power and reduce noise.

  The transmission between the loop part 1202a and the conductor 1202b is, for example, an electromagnetic induction method in which two loop parts are opposed to each other, an electromagnetic resonance method by LC resonance in which the resonance frequency is determined by inductance and capacitance, and the resonance frequency is determined by the line length of the pattern conductor. Electromagnetic resonance, coupling by capacitance between conductors, etc. can be used.

  The conversion unit 1203 may be the magnetoresistive element 205. When the high frequency output generated by the oscillation unit 101 at the time interval of the signal value “1” is input to the magnetoresistive effect element 205 via the loop part 1202a and the conductor 1202b, the magnetoresistive effect element 205 is caused by the spin torque FMR effect. Convert high frequency output to DC output. That is, the signal value “1” transmitted as a high frequency output is demodulated.

  By disposing the magnetoresistive effect element 205 so that a magnetic field generated by the loop portion 1202a and the conductor 1202b can be applied, a mechanism for applying the magnetic field to the magnetoresistive effect element 205 can be reduced in size or unnecessary, and transmission / reception can be performed. The device can be downsized.

  In the thirteenth embodiment, the case where the oscillator according to the second embodiment is used as the oscillator 1201a has been described. The receiver described in Embodiment 9 can be used as the receiver 1201b. That is, it is possible to configure the transmission / reception device with the same configuration of the oscillator and the receiver, or it is also possible to configure the transmission / reception device with the configuration of the oscillator and the receiver different from each other. In these transmission / reception apparatuses, a conductor portion to which a magnetic field is applied is also used as an antenna used for wireless transmission. Therefore, it is not necessary to newly provide an antenna for wireless transmission, and the transmission / reception apparatus can be downsized. Here, the antenna includes not only an antenna used for communication over a distance sufficiently larger than a wavelength but also an antenna, a resonator, and other wireless transmission units used for communication over a distance equal to or smaller than the wavelength. .

  Further, the present embodiment can be applied to wireless power feeding. If the signal value is always “1”, the oscillation signal, that is, the energy is always supplied to the receiver 1201b, so that wireless power can be supplied.

  The oscillator or rectifier, the transmission device or the rectification device, and the transmission / reception device according to the present invention can be used for wireless communication, wireless power feeding, and the like.

DESCRIPTION OF SYMBOLS 101 ... Oscillating part, I ... Current, 103 ... Conductor, 103a ... Conductor that flows current into the oscillating part, 103b ... Conductor that flows current from the oscillating part, 104 ... Current amplification part, H ... Magnetic field, 205 ... Magnetoresistive effect element, 502 ... inductor, 601 ... magnet, H _{AC ...} field, 1101, 1102 ... electric circuit, 1104 ... inductor, 1201a ... oscillator, 1201b ... receiver, 1202a ... loop portion, 1202b ... conductor, 1203 ... converting portion

Claims (12)

An oscillation unit whose oscillation frequency is variable by a magnetic field;
An oscillator having a conductor connected to the oscillation unit,
The oscillating unit and the conductor are arranged such that a current flowing through the conductor is larger than a current flowing through the oscillating unit, and a magnetic field generated by a current flowing through the conductor is applied to the oscillating unit. Features an oscillator. An oscillation unit whose oscillation frequency is variable by a magnetic field;
A current amplifier for amplifying the current;
An oscillator having a magnetic field application unit for applying a magnetic field to the oscillation unit,
The current amplifying unit has an input end and an output end,
Amplifies the current input from the input end and outputs it to the output end;
The oscillator is connected in series to the input end,
The oscillator, wherein the magnetic field application unit is connected in series to the output end. An oscillation unit whose oscillation frequency is variable by a magnetic field;
A current amplifier for amplifying the current;
An oscillator having a magnetic field application unit for applying a magnetic field to the oscillation unit,
The current amplifying unit has an input end and an output end,
Amplifies the current input from the input end and outputs it to the output end;
The oscillation unit and the current amplification unit are connected in parallel,
The oscillator, wherein the magnetic field application unit is connected in series to the output end. The threshold magnetic field for the oscillation unit to start oscillating is greater than zero,
The oscillator according to claim 1, wherein the magnetic field is larger than the threshold magnetic field.   The oscillator according to any one of claims 1 to 3, wherein the oscillating unit is a filtered oscillator having a magnetoresistive element, a Josephson element, or a magnetic resonance filter. A rectification unit whose rectification frequency is variable by a magnetic field;
A rectifier having a conductor connected to the rectifying unit,
The rectifying unit and the conductor are arranged such that a current flowing through the conductor is larger than a current flowing through the rectifying unit, and a magnetic field generated by a current flowing through the conductor is applied to the rectifying unit. Rectifier featured. A rectification unit whose rectification frequency is variable by a magnetic field;
A current amplifier for amplifying the current;
A rectifier having a magnetic field applying unit for applying a magnetic field to the rectifying unit,
The current amplifying unit has an input end and an output end,
Amplifies the current input from the input end and outputs it to the output end;
The rectifier is connected in series to the input end,
The rectifier, wherein the magnetic field application unit is connected in series to the output end. A rectifying unit whose oscillation frequency is variable by a magnetic field;
A current amplifier for amplifying the current;
A rectifier having a magnetic field applying unit for applying a magnetic field to the rectifying unit,
The current amplifying unit has an input end and an output end,
Amplifies the current input from the input end and outputs it to the output end;
The rectification unit and the current amplification unit are connected in parallel,
The rectifier, wherein the magnetic field application unit is connected in series to the output end. The threshold magnetic field for the rectifying unit to develop a rectifying action is greater than zero,
The rectifier according to any one of claims 6 to 8, wherein the magnetic field is larger than the threshold magnetic field.   The rectifier according to any one of claims 6 to 8, wherein the rectifying unit is a magnetoresistive effect element or a Josephson element. An oscillator according to claim 1;
A rectifier according to claim 6;
A transmission / reception apparatus that performs wireless communication or wireless power transmission by electromagnetically coupling the conductor of the oscillator and the conductor of the rectifier. An oscillator according to claim 2 or 3,
A rectifier according to claim 7 or 8,
A transmission / reception apparatus that performs wireless communication or wireless power transmission by electromagnetically coupling the magnetic field application unit of the oscillator and the magnetic field application unit of the rectifier.

Images