A magnetic field sensitive detection device and method based on gain resonant cavity-magnetic resonance coupling

Abstract

The application relates to a magnetic field sensitive detection device and method based on gain resonant cavity-magnetic resonance coupling, which comprises a microwave gain resonant cavity, a magnetic field probe, a coaxial cable, a phase shifter and a signal reading system; the magnetic field probe is connected in series with the microwave gain resonant cavity through the coaxial cable and the phase shifter, and a detection signal is read from an output end of the microwave gain resonant cavity; the microwave gain resonant cavity converts a change amount of a magnetic field into frequency movement of radiated microwaves through coupling with the magnetic field probe; the magnetic field probe is used for sensing changes of the magnetic field; the coaxial cable and the phase shifter are used for mediating long-range coupling between the microwave gain resonant cavity and the magnetic field probe, and accurately regulating the strength and phase of the coupling; and the signal reading system is used for detecting an oscillation frequency of the microwave gain resonant cavity. The application utilizes a hybrid mode, and the super-high response rate of the hybrid mode to an external magnetic field makes the detection system able to cause great changes of a resonance frequency even when the detection system is subjected to weak magnetic field changes.

Description

Technical Field

[0001] This invention relates to a magnetic field sensitive detection device and method based on gain resonant cavity-magnetic resonance coupling, belonging to the field of magnetic field detection technology. Background Technology

[0002] Currently, magnetometers used to detect weak magnetic fields are widely used in scientific research, medical diagnosis, military, archaeology, and mineral exploration. Mature magnetometers include fluxgate magnetometers, superconducting quantum interference devices (SQUs), diamond color center magnetometers, and atomic magnetometers. These magnetometers are limited by their working principles and are suitable for different scenarios. In terms of detection sensitivity alone, the most sensitive magnetometer is currently the atomic magnetometer based on the spin-free exchange relaxation (SERF) state of alkali metal atomic vapor. Its detection sensitivity can reach below fT / √Hz, thus playing a crucial role in ultra-high precision magnetic field measurements. The SERF state is a special state of alkali metal atomic vapor. It refers to a magnetic resonance with extremely low linewidth formed in alkali metal atomic vapor when the spin exchange rate between alkali metal atoms is much greater than the Larmor precession frequency. There are two core parameters that determine the detection sensitivity of a SERF magnetometer: one is the resonant linewidth of the SERF state, which is only 200 Hz, and the other is the rate of change of the SERF state frequency with respect to the external magnetic field, which is 28 GHz / T. The former reflects the limiting resolution of the SERF state in the spectrum, while the latter reflects the response of the SERF state to changes in the external magnetic field. One is determined by the intrinsic properties of the SERF state, and the other by the electron charge-to-mass ratio; both are difficult to further optimize.

[0003] To develop a magnetic field measurement technique that is more sensitive than the SERF magnetometer, a feasible direction is to find new spin states and thus break through the two core parameters of the SERF state. Summary of the Invention

[0004] In view of the current status of sensitive magnetic detection technology, this invention utilizes a coupling system composed of a gain resonant cavity and magnetic materials to develop a weak magnetic field sensitive detection device and method with a finer resonant linewidth and a higher external magnetic field response rate compared to the SERF magnetometer.

[0005] The main technical problems solved by this invention are: first, reducing the radiation linewidth of the device to the Hz level, thereby improving the device's spectral resolution limit; second, increasing the device's responsivity to external magnetic fields to more than 40 times the electron spin-gyromagnetic ratio (28 GHz / T). Here, the magnetic field responsivity refers to the change in the device's resonant frequency corresponding to a unit change in magnetic field.

[0006] Terminology Explanation:

[0007] HackRF One is a handheld microwave receiver and transmitter with spectrum analysis capabilities, primarily used by radio enthusiasts.

[0008] The technical solution of this invention is as follows:

[0009] A magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling includes:

[0010] Microwave gain resonant cavity, magnetic field probe, coaxial cable, phase shifter and signal readout system;

[0011] The magnetic field probe is connected in series with the microwave gain resonant cavity via a coaxial cable and a phase shifter, and the detection signal is read from the output of the microwave gain resonant cavity;

[0012] The microwave gain resonant cavity, through coupling with the magnetic field probe, converts changes in the magnetic field into frequency shifts in the radiated microwaves; it plays a role in information conversion within the entire measurement device.

[0013] A magnetic field probe is used to sense changes in the magnetic field. When the strength and polarity of the external magnetic field change, the magnetic resonance frequency of the magnetic field probe shifts. Through the coupling between the magnetic field probe and the microwave gain resonant cavity, the change in the magnetic resonance frequency leads to a change in the frequency of microwaves radiated by the gain resonant cavity. By measuring the frequency shift of microwaves radiated by the gain resonant cavity using a spectrum analyzer, the change in the external magnetic field can be calculated.

[0014] Coaxial cables and phase shifters are both broadband devices used to mediate long-range coupling between microwave gain resonant cavities and magnetic field probes, and to precisely control the strength and phase of the coupling.

[0015] The signal readout system is used to detect the oscillation frequency of the microwave gain resonant cavity.

[0016] The magnetic field sensitive detection device of this invention utilizes a hybrid mode generated by long-range coupling between a gain resonant cavity and magnetic resonance. The ultra-low linewidth of the gain resonant cavity ensures the ultra-high resolution of the frequency spectrum, while the ultra-high responsivity of the hybrid mode to external magnetic fields allows the detection system to exhibit significant changes in the resonant frequency even under weak magnetic field variations.

[0017] According to a preferred embodiment of the present invention, the microwave gain resonant cavity includes a resonant device and a gain circuit;

[0018] The coupling between the gain circuit and the resonant device is achieved through direct electrical conduction, or through capacitive or inductive coupling.

[0019] More preferably, the resonant device is any one of a stripline resonator, a split ring resonator, a dielectric resonator, or a microwave cavity.

[0020] The gain circuit can be any one of the following: common-collector amplifier circuit, common-emitter amplifier circuit, common-base amplifier circuit, or operational amplifier circuit.

[0021] According to a preferred embodiment of the present invention, the frequency of the microwave gain resonant cavity is adjustable within a certain range; the adjustment method includes integrating a variable capacitor in the resonant cavity and installing a coupling screw, a variable inductor, or a piezoelectric element.

[0022] According to a preferred embodiment of the present invention, the magnetic field probe includes a microwave excitation unit, a magnetic material, and a bias magnetic field;

[0023] A microwave field is radiated onto a magnetic material through a microwave excitation unit; the magnetic material generates ferromagnetic resonance under microwave drive; and a bias magnetic field generates a stable magnetic field.

[0024] More preferably, the microwave excitation unit is any one of a microstrip line, a coplanar waveguide, a planar antenna, a coaxial cable, or a loop antenna; the magnetic material is any one of yttrium iron garnet, iron oxide, permalloy, or cobalt-zirconium alloy; and the bias magnetic field is any one of neodymium iron boron magnet, ferrite magnet, or electromagnetic coil.

[0025] According to a preferred embodiment of the present invention, the signal readout system is any one of a vector network analyzer, a signal analyzer, a HackRF One, and an oscilloscope.

[0026] A magnetic field sensitive detection method based on gain resonant cavity-magnetic resonance coupling, implemented by the aforementioned magnetic field sensitive detection device, includes:

[0027] Inside the microwave gain resonant cavity, when the gain is greater than the energy dissipation of the microwave gain resonant cavity, the microwave resonance mode of the microwave gain resonant cavity reaches a self-sustaining state, that is, the microwave gain resonant cavity maintains stable oscillation and radiates microwaves of a stable frequency to the outside of the cavity; at this time, the microwave radiation spectral linewidth of the microwave gain resonant cavity reaches the order of 1 Hz.

[0028] The microwave gain resonant cavity and the magnetic material in the magnetic field probe are connected by a coaxial cable and a phase shifter. The microwave resonance mode in the microwave gain resonant cavity and the magnetic resonance mode in the magnetic material are strongly coupled over a long distance through the coaxial cable, thus forming a microwave-magnetic hybrid mode (as shown in Figure 2(b)). The coupling state between the microwave resonance mode and the magnetic resonance mode is precisely controlled by the phase shifter. When this coupling is adjusted to a critical state, a slight change in the external magnetic field drastically alters the microwave radiation frequency, achieving sensitive detection of the weak magnetic field. The frequency dependence of the hybrid mode generated after the microwave resonance and magnetic resonance coupling with the external magnetic field is shown by the purple line in Figure 2. At 142 mT in the figure, the frequency of the hybrid mode has a nearly vertical response to a slight change in the external magnetic field. In this region, a slight change in the magnitude of the magnetic field will cause a drastic change in the frequency of the hybrid mode. This frequency change rate can be more than 100 times the electron gyromagnetic ratio (red line in the figure). The hybrid mode remains in a self-sustaining state throughout the operation of the detection system, continuously radiating a single-frequency microwave signal. By detecting the frequency of the radiated microwaves, the change in the magnetic field can be calculated.

[0029] More preferably, the coupling state between the microwave resonance mode and the magnetic resonance mode is precisely controlled by a phase shifter; including:

[0030] The microwave resonance mode and the magnetic resonance mode are strongly coupled over a long distance through electromagnetic traveling waves in a coaxial cable. During the process of microwave resonance transferring energy to magnetic resonance and magnetic resonance returning energy to microwave resonance, the length of the cable determines the transmission phase of the coupling strength. The magnitude of the transmission phase determines the coupling state between the microwave resonance mode and the magnetic resonance mode. The phase shifter precisely controls the transmission phase. Therefore, the coupling between the microwave resonance mode and the magnetic resonance mode can be controlled by the phase shifter.

[0031] The beneficial effects of this invention are as follows:

[0032] 1. Ultra-high sensitivity: By suppressing the phase noise of the gain resonant cavity, its radiation spectral linewidth can reach 1Hz. The hybrid mode generated by the coupling of microwave resonance mode and magnetic resonance mode has a responsivity to external magnetic fields that is much higher than the gyromagnetic ratio of electron spin. Based on these two indicators, the detection sensitivity of this invention can outperform current SERF state magnetometers.

[0033] 2. Low cost: The phase shifter, microwave cable, resonant cavity and magnetic material used in this invention are all commercially available products and do not require additional research and development.

[0034] 3. Easy Integration: The resonant cavity, microwave cable, and phase shifter used in this invention can be planar microwave devices. These planar structures can be fabricated using micro-nano processes, reducing their size to the micrometer level. Furthermore, this invention does not have high requirements for the volume of magnetic materials; micrometer-sized magnetic particles can be used. This invention can either integrate the resonant cavity, microwave circuitry, and magnetic materials into a single device, or integrate the resonant cavity and magnetic field probe separately.

[0035] 4. Simple structure: This invention does not require a complex optical path, and the detection signal can be read out electrically. Furthermore, this invention can operate at room temperature without the need for additional heating or cooling devices. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling of the present invention;

[0037] Figure 2(a) is a schematic diagram of the radiation spectrum of the gain resonator;

[0038] Figure 2(b) is a schematic diagram showing the variation trend of the hybrid mode (purple solid line) formed by the coupling of microwave resonance mode (green dashed line) and magnetic resonance mode (blue dashed line) with the external magnetic field. Detailed Implementation

[0039] The present invention will be further defined below with reference to the accompanying drawings and embodiments, but is not limited thereto.

[0040] Example 1

[0041] A magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling, such as Figure 1 As shown, it includes:

[0042] Microwave gain resonant cavity, magnetic field probe, coaxial cable, phase shifter and signal readout system;

[0043] The magnetic field probe is connected in series with the microwave gain resonant cavity via a coaxial cable and a phase shifter, and the detection signal is read from the output of the microwave gain resonant cavity;

[0044] The microwave gain resonant cavity, through coupling with the magnetic field probe, converts changes in the magnetic field into frequency shifts in the radiated microwaves; it plays a role in information conversion within the entire measurement device.

[0045] A magnetic field probe is used to sense changes in the magnetic field. When the strength and polarity of the external magnetic field change, the magnetic resonance frequency of the magnetic field probe shifts. Through the coupling between the magnetic field probe and the microwave gain resonant cavity, the change in the magnetic resonance frequency leads to a change in the frequency of microwaves radiated by the gain resonant cavity. By measuring the frequency shift of microwaves radiated by the gain resonant cavity using a spectrum analyzer, the change in the external magnetic field can be calculated.

[0046] Coaxial cables and phase shifters are both broadband devices used to mediate long-range coupling between microwave gain resonant cavities and magnetic field probes, and to precisely control the strength and phase of the coupling.

[0047] The signal readout system is used to detect the oscillation frequency of the microwave gain resonant cavity.

[0048] The magnetic field sensitive detection device of this invention utilizes a hybrid mode generated by long-range coupling between a gain resonant cavity and magnetic resonance. The ultra-low linewidth of the gain resonant cavity ensures the ultra-high resolution of the frequency spectrum, while the ultra-high responsivity of the hybrid mode to external magnetic fields allows the detection system to exhibit significant changes in the resonant frequency even under weak magnetic field variations.

[0049] Example 2

[0050] The magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling described in Example 1 differs in that:

[0051] A microwave gain resonant cavity includes resonant devices and gain circuitry.

[0052] The coupling between the gain circuit and the resonant device is achieved through direct electrical conduction, or through capacitive or inductive coupling.

[0053] The resonant device is any one of the following: stripline resonator, split ring resonator, dielectric resonator, and microwave cavity.

[0054] The gain circuit can be any one of the following: common-collector amplifier circuit, common-emitter amplifier circuit, common-base amplifier circuit, or operational amplifier circuit.

[0055] The frequency of the microwave gain resonant cavity can be adjusted within a certain range; adjustment methods include integrating a variable capacitor in the resonant cavity, installing coupling screws, variable inductors, or piezoelectric elements.

[0056] The magnetic field probe includes a microwave excitation unit, magnetic materials, and a bias magnetic field;

[0057] A microwave field is radiated onto a magnetic material through a microwave excitation unit; the magnetic material generates ferromagnetic resonance under microwave drive; and a bias magnetic field generates a stable magnetic field.

[0058] The microwave excitation unit is any one of microstrip line, coplanar waveguide, planar antenna, coaxial cable, or loop antenna; the magnetic material is any one of yttrium iron garnet, iron oxide, permalloy, or cobalt-zirconium alloy; and the bias magnetic field is any one of neodymium iron boron magnet, ferrite magnet, or electromagnetic coil.

[0059] The signal readout system can be any one of a vector network analyzer, signal analyzer, HackRF One, or oscilloscope.

[0060] Example 3

[0061] A magnetic field sensitive detection method based on gain resonant cavity-magnetic resonance coupling, implemented by the magnetic field sensitive detection device described in Example 1 or 2, includes:

[0062] Inside the microwave gain resonant cavity, when the gain is greater than the energy dissipation of the microwave gain resonant cavity, the microwave resonance mode of the microwave gain resonant cavity reaches a self-sustaining state, that is, the microwave gain resonant cavity maintains stable oscillation and radiates microwaves of a stable frequency to the outside of the cavity; at this time, the microwave radiation spectral linewidth of the microwave gain resonant cavity reaches the order of 1 Hz.

[0063] The microwave gain resonant cavity and the magnetic material in the magnetic field probe are connected by a coaxial cable and a phase shifter. The microwave resonance mode in the microwave gain resonant cavity and the magnetic resonance mode in the magnetic material are strongly coupled over a long distance through the coaxial cable, thus forming a microwave-magnetic hybrid mode (as shown in Figure 2(b)). The coupling state between the microwave resonance mode and the magnetic resonance mode is precisely controlled by the phase shifter. When this coupling is adjusted to a critical state, a slight change in the external magnetic field drastically alters the microwave radiation frequency, enabling sensitive detection of weak magnetic fields. The frequency dependence of the hybrid mode generated after the coupling of microwave resonance and magnetic resonance with the external magnetic field is shown by the purple line in Figure 2(b). At 142 mT in the figure, the frequency of the hybrid mode has a nearly vertical response to a slight change in the external magnetic field. In this region, a slight change in the magnitude of the magnetic field will cause a drastic change in the frequency of the hybrid mode. This frequency change rate can be more than 100 times the electron gyromagnetic ratio (red line in the figure). The hybrid mode remains in a self-sustaining state throughout the operation of the detection system, continuously radiating a single-frequency microwave signal. By detecting the frequency of the radiated microwaves, the change in the magnetic field can be calculated.

[0064] The coupling state between the microwave resonance mode and the magnetic resonance mode is precisely controlled by a phase shifter; including:

[0065] The microwave resonance mode and the magnetic resonance mode are strongly coupled over a long distance through electromagnetic traveling waves in a coaxial cable. During the process of microwave resonance transferring energy to magnetic resonance and magnetic resonance returning energy to microwave resonance, the length of the cable determines the transmission phase of the coupling strength. The magnitude of the transmission phase determines the coupling state between the microwave resonance mode and the magnetic resonance mode. The phase shifter precisely controls the transmission phase. Therefore, the coupling between the microwave resonance mode and the magnetic resonance mode can be controlled by the phase shifter.

[0066] Figure 2(a) is a schematic diagram of the radiation spectrum of the gain resonant cavity; the horizontal axis of Figure 2(a) represents the frequency measurement range of the radiation spectrum in the experiment, expressed as radiation frequency (ω). c The origin is [-7, 7] Hz, and the measurement range is [-7, 7]. The vertical axis represents the power of the radiation spectrum. By suppressing the phase noise of the microwave gain resonator, its radiation spectral linewidth can be reduced to below 1 Hz.

[0067] Figure 2(b) shows the variation trend of the hybrid mode (purple solid line) formed by the coupling of the microwave resonance mode (green dashed line) and the magnetic resonance mode (blue dashed line) with the external magnetic field. The horizontal axis of Figure 2(b) represents the magnitude of the external static magnetic field applied to the magnetic field probe in the demonstration experiment. This magnetic field range is not fixed and depends on the probe design. The left vertical axis represents the detection range of the radiation spectrum in the demonstration experiment, and the right vertical axis represents the ratio of the hybrid mode's responsivity to the external magnetic field relative to the electron gyromagnetic ratio (28 GHz / T). In the hybrid mode, the frequency responsivity to the external magnetic field is a multiple of the electron gyromagnetic ratio (red solid line).

[0068] By using a gain circuit to compensate for the energy loss of the microwave gain resonator, the microwave gain resonator can maintain a stable oscillation state while radiating microwaves outward. When there is no coupling between the microwave gain resonator and the microwave resonance, the frequency of the radiated microwaves is determined solely by the internal structure of the microwave gain resonator, and is a fixed frequency that does not change with the magnetic field (green dashed line in Figure 2(b)). By suppressing the phase noise of the microwave gain resonator through a feedback loop, the radiation spectral linewidth of the microwave gain resonator can be reduced to 1 Hz.

[0069] A microwave gain resonant cavity is connected to a magnetic field probe via microwave circuitry, including microstrip lines, coaxial cables, and phase shifters, enabling long-range coupling between the microwave resonant mode and the magnetic resonant mode. While the microwave resonance of the resonant cavity is insensitive to changes in the external magnetic field, the magnetic resonance does respond to such changes. Therefore, the hybrid system formed by this long-range, strong coupling exhibits a sensitive response to external magnetic fields.

[0070] By precisely adjusting the transmission phase between the microwave gain resonant cavity and the magnetic field probe, the mixed state formed by the coupling of microwave resonance and magnetic resonance is tuned to a critical coupling state (as shown by the purple solid line in Figure 2(b)). The response rate of the mixed state to an external magnetic field within a specific magnetic field range can be much greater than the response rate of electron spin resonance to an external magnetic field (as shown by the red solid line in Figure 2(b)). Utilizing this characteristic of the mixed state, sensitive detection of external magnetic fields can be achieved.

Claims

1. A magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling, characterized in that, include: Microwave gain resonant cavity, magnetic field probe, coaxial cable, phase shifter and signal readout system; The magnetic field probe is connected in series with the microwave gain resonant cavity via a coaxial cable and a phase shifter, and the detection signal is read from the output of the microwave gain resonant cavity; The microwave gain resonant cavity, through coupling with the magnetic field probe, converts changes in the magnetic field into frequency shifts in the radiated microwaves. A magnetic field probe is used to sense changes in the magnetic field. When the strength and polarity of the external magnetic field change, the magnetic resonance frequency of the magnetic field probe shifts. Through the coupling between the magnetic field probe and the microwave gain resonant cavity, the change in the magnetic resonance frequency leads to a change in the frequency of microwaves radiated by the gain resonant cavity. By measuring the frequency shift of microwaves radiated by the gain resonant cavity using a spectrum analyzer, the change in the external magnetic field can be calculated. Coaxial cables and phase shifters are used to mediate long-range coupling between the microwave gain resonant cavity and the magnetic field probe, and to precisely control the strength and phase of the coupling. By precisely adjusting the transmission phase between the microwave gain resonant cavity and the magnetic field probe, the mixed state formed by the coupling of microwave resonance and magnetic resonance is tuned to the critical coupling state. When this coupling effect is tuned to the critical state, the slight change in the external magnetic field drastically changes the microwave radiation frequency. At this time, the frequency has a nearly perpendicular response to the slight change in the external magnetic field, thus achieving sensitive detection of the weak magnetic field. The signal readout system is used to detect the oscillation frequency of the microwave gain resonant cavity; The magnetic field probe includes a microwave excitation unit, magnetic materials, and a bias magnetic field; A microwave field is radiated onto a magnetic material through a microwave excitation unit; the magnetic material then generates ferromagnetic resonance under microwave drive. A bias magnetic field generates a stable magnetic field.

2. The magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling according to claim 1, characterized in that, A microwave gain resonant cavity includes resonant devices and gain circuits.

3. The magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling according to claim 2, characterized in that, The coupling between the gain circuit and the resonant device is achieved through direct electrical conduction, or through capacitive or inductive coupling.

4. The magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling according to claim 2, characterized in that, The resonant device can be any one of a microstrip line resonator, an open resonant ring, a dielectric resonator, or a microwave resonant cavity; The gain circuit can be any one of the following: common-collector amplifier circuit, common-emitter amplifier circuit, common-base amplifier circuit, or operational amplifier circuit.

5. A magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling according to claim 2, characterized in that, The frequency of the microwave gain resonant cavity can be adjusted within a certain range.

6. The magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling according to claim 1, characterized in that, The microwave excitation unit is any one of microstrip line, coplanar waveguide, planar antenna, coaxial cable, or loop antenna; the magnetic material is any one of yttrium iron garnet, iron oxide, permalloy, or cobalt-zirconium alloy; and the bias magnetic field is any one of neodymium iron boron magnet, ferrite magnet, or electromagnetic coil.

7. A magnetic field sensitive detection device based on gain resonant cavity-magnetic resonance coupling according to any one of claims 1-6, characterized in that, The signal readout system can be any one of a vector network analyzer, signal analyzer, HackRF One, or oscilloscope.

8. A magnetic field sensitive detection method based on gain resonant cavity-magnetic resonance coupling, characterized in that, This is achieved by any one of the magnetic field sensitive detection devices described in claims 1-7, comprising: Inside the microwave gain resonant cavity, when the gain is greater than the energy dissipation of the microwave gain resonant cavity, the microwave resonance mode of the microwave gain resonant cavity reaches a self-sustaining state, that is, the microwave gain resonant cavity maintains stable oscillation and radiates microwaves of a stable frequency to the outside of the cavity; at this time, the microwave radiation spectral linewidth of the microwave gain resonant cavity reaches the order of 1 Hz. The microwave gain resonant cavity and the magnetic material in the magnetic field probe are connected by a coaxial cable and a phase shifter. The microwave resonance mode in the microwave gain resonant cavity and the magnetic resonance mode in the magnetic material are strongly coupled over a long distance through the coaxial cable, thus forming a microwave-magnetic hybrid mode. The coupling state between the microwave resonance mode and the magnetic resonance mode is precisely controlled by the phase shifter. When this coupling is adjusted to a critical state, the slight change in the external magnetic field drastically changes the microwave radiation frequency, thus achieving sensitive detection of the weak magnetic field.

9. A magnetic field sensitive detection method based on gain resonant cavity-magnetic resonance coupling according to claim 8, characterized in that, The coupling state between the microwave resonance mode and the magnetic resonance mode is precisely controlled by a phase shifter; including: The microwave resonance mode and the magnetic resonance mode are strongly coupled over a long distance through electromagnetic traveling waves in a coaxial cable. During the process of microwave resonance transferring energy to magnetic resonance and magnetic resonance returning energy to microwave resonance, the length of the cable determines the transmission phase of the coupling strength. The magnitude of the transmission phase determines the coupling state between the microwave resonance mode and the magnetic resonance mode. The phase shifter precisely controls the transmission phase. Therefore, the coupling between the microwave resonance mode and the magnetic resonance mode can be controlled by the phase shifter.

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