Quantum enhanced vector magnetic field gradient detection method and device

Abstract

The invention discloses a quantum enhanced vector magnetic field gradient detection method and device, and the method comprises the steps: generating two pairs of intensity-related twin beams through a nonlinear effect-four-wave mixing, and further constructing a pair of continuous multi-dimensional polarization entangled beams from the twin beams through a linear polarization beam splitter, i.e., carrying out the idler frequency light and signal light as detection light, respectively inputting a pair of atom sensors to realize vector magnetic field measurement. According to the invention, the continuous multi-dimensional polarization entangled light source is formed by splitting and combining twin beams, so that the intensity and direction of a vector magnetic field are accurately measured, and meanwhile, shot noise and common-mode magnetic field noise of light are remarkably reduced.

Description

Technical Field

[0001] The present invention relates to a technology in the field of physical measurement, in particular to a quantum enhanced vector magnetic field gradient detection method and device. Background Art

[0002] Precision measurement technology based on atomic magnetometers is widely used in many fields such as physics, biology, material science and geology due to its high sensitivity. With the advancement of quantum technology, all these fields require vector field measurements. Due to the Heisenberg uncertainty principle, it is impossible to perform optimal measurements of non-reciprocal parameters together, because the product of the noise of non-reciprocal parameters is a constant. In traditional quantum gradiometers, vector strength and direction are coupled to the non-reciprocal parameters, which means that while using the optimal measurement to minimize the noise of one of them, the noise of the other will be amplified, resulting in the inability to measure the other parameter. In order to optimally measure the vector magnetic field strength and direction at the same time, it is necessary to build a new light source and find the reciprocal parameter and measurement method. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention proposes a quantum enhanced vector magnetic field gradient detection method and device, which utilizes twin beam splitting to combine a continuous multi-dimensional polarization entangled light source, thereby accurately measuring the intensity and direction of the vector magnetic field while significantly reducing the shot noise and common-mode magnetic field noise of the light.

[0004] The present invention is achieved through the following technical solutions:

[0005] The present invention relates to a quantum enhanced vector magnetic field gradient detection method. After two pairs of intensity-correlated twin beams are generated through nonlinear effect-four-wave mixing, the twin beams are further constructed into a pair of continuous multi-dimensional polarization entangled beams through a linear polarization beam splitter, that is, idler light and signal light are used as detection light, which are respectively input into a pair of atomic sensors to realize vector magnetic field measurement.

[0006] The Stokes parameter correlation between the idler light and the signal light is that the first Stokes component Sx of the idler light and the first Stokes component Sx of the signal light are enhanced or weakened in intensity at the same time, and the degree of enhancement or weakening is the same; the second Stokes component Sy of the idler light and the second Stokes component Sy of the signal light are enhanced or weakened in intensity at the same time, and the degree of enhancement or weakening is the same; the third Stokes component Sz of the idler light and the third Stokes component Sz of the signal light are enhanced in intensity while the other is weakened, and the degree of enhancement and weakening is the same.

[0007] The present invention relates to a detection device for realizing the above method, comprising: a pair of rubidium-85 atomic ensembles arranged in parallel for four-wave mixing, a pair of rubidium-87 atomic ensembles arranged in parallel for magnetic field sensing, and a Stokes parameter measurement device, wherein: the pair of rubidium-85 atomic ensembles mix the input coherent light source and seed light respectively and output idler light and signal light respectively, the first rubidium-87 atomic ensemble mixes the input idler light and coherent light source, the second rubidium-87 atomic ensemble mixes the input signal light and coherent light source, and the Stokes parameter measurement device obtains the Stokes parameter difference according to the two-way output light of the rubidium-87 atomic ensemble.

[0008] The input ends of the rubidium-85 atomic ensemble and the rubidium-87 atomic ensemble are respectively connected to four coherent light sources to receive pump light fields.

[0009] The input ends of the pair of rubidium-85 atomic ensembles are provided with polarization beam splitters to receive two paths of seed light from the same acousto-optic modulator.

[0010] The output end of the first rubidium-85 atomic ensemble is provided with a piezoelectric ceramic driver and a 1 / 2 wave plate, and the output end of the second rubidium-85 atomic ensemble is provided with a polarization beam splitter facing the 1 / 2 wave plate, and the polarization beam splitter outputs signal light to the second rubidium-87 atomic ensemble.

[0011] The output end of the second rubidium-85 atomic ensemble is provided with a piezoelectric ceramic driver and a 1 / 2 wave plate, and the output end of the first rubidium-85 atomic ensemble is provided with a polarization beam splitter facing the 1 / 2 wave plate, and the polarization beam splitter outputs idler light to the first rubidium-87 atomic ensemble.

[0012] The Stokes parameter measurement device comprises: two pairs of 1 / 2 wave plates, a pair of polarization beam splitters, two pairs of photodetectors and a subtraction circuit, which are respectively arranged at the output ends of the first and second rubidium-87 atomic ensembles, wherein: the output light of the rubidium-87 atomic ensemble is passed through the wave plate and the polarization beam splitter to obtain two optical signals, and the four photodetectors collect and convert the obtained electrical signals respectively and then output them to the subtraction circuit, and the subtraction circuit subtracts the output results of the same rubidium-87 atomic ensemble in pairs, and then subtracts the signal light and the idler light again and outputs them. Technical Effects

[0013] The present invention constructs a continuous multi-dimensional polarization Stokes parameter simultaneous entangled light source through the four-wave mixing process in the atomic ensemble and the linear polarization beam splitter, which can perform better multi-parameter estimation than the traditional polarization entangled light. Combining this new light source with the traditional gradiometer can simultaneously measure the intensity and direction of a vector magnetic field, and reduce the shot noise and common-mode magnetic field noise of the light. Compared with the prior art, the present invention compresses the noise of the Stokes parameters to simultaneously measure the intensity and direction of a vector magnetic field. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is the principle diagram of the device of the present invention;

[0015] Figure 2 The energy level of rubidium-85 atoms and the corresponding optical frequency diagram in the embodiment;

[0016] Figure 3 The energy level of rubidium-87 atoms and the corresponding optical frequency diagram in the embodiment;

[0017] Figure 4 A schematic diagram of a magnetometer in an embodiment;

[0018] Figure 5 Schematic diagram of a Stokes parameter measurement device in an embodiment;

[0019] Figure 6 It is the principle diagram of the present invention;

[0020] Figure 7 It is an effect diagram of the embodiment;

[0021] In the figure: a first coherent light source 1, a second coherent light source 2, a third coherent light source 3, a fourth coherent light source 4, a first seed light 5, a second seed light 6, a first component signal light 7, a second component signal light 8, a first component idler light 9, a second component idler light 10, an idler light 11, a signal light 12, a first rubidium-85 atomic ensemble 13, a second rubidium-85 atomic ensemble 14, a first rubidium-87 atomic ensemble 15, a second rubidium-87 atomic ensemble 16, a first acousto-optic modulator 17, a second acousto-optic modulator 18, a first polarization beam splitter 19, a second polarization beam splitter 20, a third polarization beam splitter 21, and a fourth polarization beam splitter 22, fifth polarization beam splitter 23, sixth polarization beam splitter 24, first light baffle 25, second light baffle 26, first piezoelectric ceramic driver 27, second piezoelectric ceramic driver 28, first 1 / 2 wave plate 29, second 1 / 2 wave plate 30, third 1 / 2 wave plate 31, fourth 1 / 2 wave plate 32, first 1 / 4 wave plate 33, second 1 / 4 wave plate 34, third 1 / 4 wave plate 35, fourth 1 / 4 wave plate 36, first photodetector 37, second photodetector 38, third photodetector 39, fourth photodetector 40, first subtractor 41, second subtractor 42, third subtractor 43. DETAILED DESCRIPTION

[0022] like Figure 1 , Figure 4 and Figure 5As shown, this embodiment relates to a quantum enhanced vector magnetic field gradient detection device, comprising: a first rubidium-85 atomic ensemble 13 for four-wave mixing, a second polarization beam splitter 20, a first rubidium-87 atomic ensemble 15 for magnetic field sensing, a third 1 / 2 wave plate 31, a third 1 / 4 wave plate 35 and a fifth polarization beam splitter 23, which are sequentially arranged to constitute a first branch; and a second rubidium-85 atomic ensemble 14 for four-wave mixing, a third polarization beam splitter 21, a second rubidium-87 atomic ensemble 16 for magnetic field sensing, a fourth 1 / 2 wave plate 32, a fourth 1 / 4 wave plate 36 and a sixth polarization beam splitter 24, which are sequentially arranged to constitute a second branch. A first coherent light source 1 and a second coherent light source 2 are respectively provided therein, a first acousto-optic modulator 17 and a first polarization beam splitter 19 for generating seed light are arranged at the input ends of the rubidium-85 atomic ensemble 13 and 14, a second acousto-optic modulator 18, a fourth polarization beam splitter 22 and a pair of 1 / 4 wave plates 33 and 34 constitute a magnetometer for generating coherent light sources 3 and 4 input to the rubidium-87 atomic ensemble, two pairs of 1 / 2 wave plates 31, 32, 35, 36, a fifth and a sixth polarization beam splitter 23 and 24, four photodetectors 37-40 respectively arranged on the exit surfaces of the polarization beam splitters and three subtraction circuits 41-43 respectively connected to the photodetectors constitute a Stokes parameter measurement device.

[0023] The first coherent light source 1 and the second coherent light source 2 are two pump light fields for generating a four-wave mixing process, wherein the first coherent light source 1 is the pump light field in the first rubidium-85 atomic ensemble 13, and the second coherent light source 2 is the pump light field in the second rubidium-85 atomic ensemble 14.

[0024] The third coherent light source 3 and the fourth coherent light source 4 are respectively two pump light fields of the magnetic field gradiometer, wherein: the third coherent light source 3 is the pump light field in the first rubidium-87 atomic ensemble 15, and the fourth coherent light source 4 is the pump light field in the second rubidium-87 atomic ensemble 16.

[0025] The seed light, i.e. the first seed light 5 and the second seed light 6, are two seed light fields that produce the four-wave mixing process, wherein: the first seed light 5 is the seed light field in the first rubidium-85 atomic ensemble 13, and the second seed light 6 is the seed light field in the second rubidium-85 atomic ensemble 14.

[0026] The first component signal light 7 and the second component signal light 8 received by the second rubidium-87 atomic ensemble 16 are respectively two signal light fields amplified by the four-wave mixing process; the first component signal light 7 is the signal light field amplified by the first seed light 5 and the first coherent light source 1 in the first rubidium-85 atomic ensemble 13 through the nonlinear effect-four-wave mixing process, and the second component signal light 8 is the signal light field amplified by the second seed light 6 and the second coherent light source 2 in the second rubidium-85 atomic ensemble 14 through the nonlinear effect-four-wave mixing process. The two component signal lights 7 and 8 are combined to generate a signal light field through the third polarization beam splitter 21.

[0027] The output ends of the first and second rubidium-85 atomic ensembles are respectively provided with a piezoelectric ceramic driver and a 1 / 2 wave plate for adjusting the phase and / or linear polarization direction of the first and second component signal lights 7, 10;

[0028] The quarter wave plates 33 and 34 in the magnetometer are used to adjust the elliptical polarization rates of the third coherent light source 3 and the fourth coherent light source 4 respectively.

[0029] The two pairs of wave plates 31, 32, 35, and 36 in the Stokes parameter measurement device are respectively used to adjust the linear polarization directions of the idle light 11 passing through the first rubidium-87 atomic ensemble 15 and the signal light 32 passing through the second rubidium-87 atomic ensemble 16, as well as the elliptical polarization rates of the idle light 11 passing through the first rubidium-87 atomic ensemble 15 and the signal light 32 passing through the second rubidium-87 atomic ensemble 16.

[0030] The adjustments include:

[0031] The first coherent light source 1 and the first seed light 5 are spaced at an angle of 0.3° to 0.4°;

[0032] The second coherent light source 2 and the second seed light 6 intersect and merge at a certain angle at the center of the second rubidium-85 atomic ensemble 14;

[0033] The second coherent light source 2 and the second seed light 6 are spatially spaced at an angle of 0.3° to 0.4°.

[0034] The first component signal light 7 and the first idler light 9 are separated from the center of the first atomic ensemble 13 at an angle of 0.6° to 0.8°;

[0035] The second component signal light 8 and the second idler light 10 are distributed at equal angles on both sides of the second coherent light source 2;

[0036] The second component signal light 8 and the second idler light 10 are separated from the center of the second atomic ensemble 14 at an angle of 0.6° to 0.8°.

[0037] The polarization direction of the first component idler light 9 is perpendicular to the polarization direction of the second component idler light 10 after passing through the first 1 / 2 wave plate 29;

[0038] The phase of the first component idler light 9 is consistent with the phase of the second component idler light 10 after passing through the second piezoelectric ceramic driver 28;

[0039] The polarization direction of the first component signal light 7 after passing through the second 1 / 2 wave plate 30 is perpendicular to the polarization direction of the second component signal light 8;

[0040] The phase of the first component signal light 7 after passing through the first piezoelectric ceramic driver 27 is consistent with the phase of the second component signal light 8 .

[0041] The first acousto-optic modulator 17 detunes the frequencies of the first seed light 5 and the second seed light 6 to 3.04 GHz, the frequencies of the first coherent light source 1 and the second coherent light source 2. The frequencies of the first coherent light source 1 and the second coherent light source 2 are both 5S of rubidium-85 atoms. 1 / 2 , F=2→5P 1 / 2 Blue detuning 1 GHz; the second acousto-optic modulator 18 modulates the third coherent light 3 and the fourth coherent light 4 into pulse pump light with a duty cycle of 3%.

[0042] like Figure 2-Figure 5 As shown, this embodiment relates to a quantum enhanced vector magnetic field gradient detection method of the above device, specifically comprising:

[0043] Step 1: Inject the frequency-modulated first coherent light source 1, the first seed light 5, the second coherent light source 2, and the second seed light 6 into the first rubidium-85 atomic ensemble 13 and the second rubidium-85 atomic ensemble 14 respectively to generate four-wave mixing, and generate two pairs of entangled light with entanglement characteristics, namely the first component signal light 7, the first idler light 9 and the second component signal light 8, and the second idler light 10.

[0044] Step 2: The first idler light 9 and the second idler light 10 are combined into an idler light 11 by the second polarization beam splitter 20; the first component signal light 7 and the second component signal light 8 are combined into a signal light 12 by the second polarization beam splitter 21. The idler light 11 and the signal light 12 are the multi-dimensional polarization entangled light sources desired by the present invention. At the same time, the polarization and compression direction thereof can be modulated by the first piezoelectric ceramic driver 27 and the second piezoelectric ceramic driver 28.

[0045] Step 3: First, the polarization-modulated third coherent light source 3 and the fourth coherent light source 4 are injected into the first rubidium-87 atomic ensemble 15 and the second rubidium-87 atomic ensemble 16 for optical pumping. The magnetic field to be measured is simulated by the surrounding Helmholtz coils.

[0046] Step 4: Inject the signal light 12 and idler light 11 of the multidimensional polarization entangled light source into the first rubidium-87 atomic ensemble 15 and the second rubidium-87 atomic ensemble 16 respectively, and couple the magnetic field information to the Stokes parameter of the multidimensional polarization entangled light source through the atoms. Figure 5 In the Stokes parameter detection system shown, the Stokes parameters of the multi-dimensional polarization entangled light source are detected and analyzed to obtain the magnetic field information.

[0047] After specific actual experiments, the power of the first coherent light source 1 and the second coherent light source 2 are both 110mW, and the power of the first seed light 5 and the second seed light 6 are both 15μW. The temperature of the first rubidium-85 atomic ensemble 13 and the second rubidium-85 atomic ensemble 14 are both 120°. The frequencies of the first seed light 5 and the second seed light 6 are detuned from the frequency of the first coherent light source 1 and the second coherent light source 2 by 3.04GHz. The first coherent light source 1 and the first seed light 5, as well as the second coherent light 2 and the second seed light 6 are spatially 0.4°. The Larmor frequency of the magnetic field is 80kHz. The temperature of the first rubidium-87 atomic ensemble 15 and the second rubidium-87 atomic ensemble 16 are both 35°, which is room temperature. The frequencies of the first coherent light source 1 and the second coherent light source 2 are both 5S of rubidium-85 atoms. 1 / 2 , F=2→5P 1 / 2 Blue detuning 1GHz; the third coherent light 3 and the fourth coherent light 4 are modulated as pulsed pump light with a duty cycle of 3%. The power of the third coherent light 3 and the fourth coherent light 4 is 5mW. The experimental data that can be obtained are: the detection of the magnetic field intensity obtained 6fT / cm / Hz at a magnetic field frequency of 20Hz 1 / 2 Sensitivity; the detection of magnetic field strength was 6μrad / cm / Hz 1 / 2 sensitivity.

[0048] like Figure 2 The following is the energy level of rubidium-85 atoms and the corresponding optical frequency diagram during the four-wave mixing process. 1 / 2、 5P 1 / 2 is the fine structure of rubidium-85 atoms, where F=1 and F=2 are the fine structure 5S 1 / 2 The first component signal light and the first component idler light red (blue) are detuned to the first coherent light source 1GHz (5S 1 / 2 , F=2→5P 1 / 2 , F'=2); the second component signal light and the second component idler light red (blue) are detuned to the second coherent light source 1GHz (5S 1 / 2 , F=2→5P 1 / 2 , F'=3).

[0049] like Figure 3The figure shows the energy level of rubidium-87 atoms and the corresponding optical frequency diagram during the nonlinear magneto-optical rotation process. 1 / 2、 5P 1 / 2 is the fine structure of rubidium-87 atoms, where F=1 and F=2 are the fine structure 5S 1 / 2 The signal light blue is detuned to the fourth coherent light source 2GHz, (5S 1 / 2 , F=2→5P 1 / 2 , F'=2); the idler blue is detuned to the third coherent light source 8GHz (5S 1 / 2 , F=2→5P 1 / 2 , F'=3).

[0050] like Figure 7 As shown, the dotted line represents the optimal sensitivity of the entangled gradiometer, and the X signal amplitude of the vector magnetometer (left ordinate) and the noise power relative to the light field particle noise (right ordinate) vary with Q. The black circle and blue circle represent the experimental data, respectively. The red line represents the result of fitting with the Aocos (OB) function, where Ao = 6.9. The blue dotted line and the blue solid line represent the theoretical simulation of PSN and relative noise power, respectively. The noise of the three Stokes parameters of the signal light 12 and the idler light 11 of the multi-dimensional polarization entangled light source can be compressed by 6dB simultaneously relative to the noise of the classical light source. This enables the detection of the magnetic field intensity to obtain 6fT / cm / Hz at a magnetic field frequency of 20Hz. 1 / 2 Sensitivity; the detection of magnetic field strength was 6μrad / cm / Hz 1 / 2 Sensitivity

[0051] Compared with the prior art, the present invention constructs a multi-dimensional polarization entangled light source to accurately measure the intensity and direction of the vector magnetic field, while significantly reducing the shot noise and common-mode magnetic field noise of the light.

[0052] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principle and purpose of the present invention. The protection scope of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. Each implementation scheme within its scope shall be subject to the constraints of the present invention.

Claims

1. A quantum enhanced vector magnetic field gradient detection method, characterized in that: After two pairs of intensity-correlated twin beams are generated through nonlinear effect-four-wave mixing, the twin beams are further constructed into a pair of continuous multi-dimensional polarization entangled beams through a linear polarization beam splitter, that is, the idler light and the signal light are used as detection light, which are respectively input into a pair of atomic sensors to realize vector magnetic field measurement; The Stokes parameter correlation between the idler light and the signal light is that the first Stokes component Sx of the idler light and the first Stokes component Sx of the signal light are enhanced or weakened in intensity at the same time, and the degree of enhancement or weakening is the same; the second Stokes component Sy of the idler light and the second Stokes component Sy of the signal light are enhanced or weakened in intensity at the same time, and the degree of enhancement or weakening is the same; the third Stokes component Sz of the idler light and the third Stokes component Sz of the signal light are enhanced in intensity while the other is weakened, and the degree of enhancement and weakening is the same.

2. A detection device for implementing the method according to claim 1, characterized in that: include: A pair of parallel rubidium-85 atomic ensembles for four-wave mixing, a pair of parallel rubidium-87 atomic ensembles for magnetic field sensing, and a Stokes parameter measurement device, wherein: a pair of rubidium-85 atomic ensembles mix input coherent light source and seed light respectively and output idler light and signal light respectively, the first rubidium-87 atomic ensemble mixes input idler light and coherent light source, the second rubidium-87 atomic ensemble mixes input signal light and coherent light source, and the Stokes parameter measurement device obtains the Stokes parameter difference according to the two output lights of the rubidium-87 atomic ensemble.

3. The detection device according to claim 2, characterized in that: The Stokes parameter measurement device comprises: two pairs of 1 / 2 wave plates, a pair of polarization beam splitters, two pairs of photodetectors and a subtraction circuit, which are respectively arranged at the output ends of the first and second rubidium-87 atomic ensembles, wherein: the output light of the rubidium-87 atomic ensemble is passed through the wave plate and the polarization beam splitter to obtain two optical signals, and the four photodetectors collect and convert the obtained electrical signals respectively and then output them to the subtraction circuit, and the subtraction circuit subtracts the output results of the same rubidium-87 atomic ensemble in pairs, and then subtracts the signal light and the idler light again and outputs them.

4. The detection device according to claim 2, characterized in that: The input ends of the rubidium-85 atomic ensemble and the rubidium-87 atomic ensemble are respectively connected to four coherent light sources to receive pump light fields; The input end of the pair of rubidium-85 atomic ensembles is provided with a polarization beam splitter to receive two paths of seed light from the same acousto-optic modulator; The output end of the first rubidium-85 atomic ensemble is provided with a piezoelectric ceramic driver and a 1 / 2 wave plate, the output end of the second rubidium-85 atomic ensemble is provided with a polarization beam splitter facing the 1 / 2 wave plate, and the polarization beam splitter outputs signal light to the second rubidium-87 atomic ensemble; The output end of the second rubidium-85 atomic ensemble is provided with a piezoelectric ceramic driver and a 1 / 2 wave plate, and the output end of the first rubidium-85 atomic ensemble is provided with a polarization beam splitter facing the 1 / 2 wave plate, and the polarization beam splitter outputs idler light to the first rubidium-87 atomic ensemble.

5. The detection device according to claim 4, characterized in that: The first coherent light source and the second coherent light source are two pump light fields for generating a four-wave mixing process, wherein the first coherent light source is the pump light field in the first rubidium-85 atomic ensemble, and the second coherent light source is the pump light field in the second rubidium-85 atomic ensemble; The third coherent light source and the fourth coherent light source are two pumping light fields of the magnetic field gradiometer, wherein: the third coherent light source is the pumping light field in the first rubidium-87 atomic ensemble, and the fourth coherent light source is the pumping light field in the second rubidium-87 atomic ensemble; The seed light, i.e. the first seed light and the second seed light, are two seed light fields that generate the four-wave mixing process, wherein: the first seed light is the seed light field in the first rubidium-85 atomic ensemble, and the second seed light is the seed light field in the second rubidium-85 atomic ensemble.

6. The detection device according to claim 3, characterized in that: The two pairs of wave plates in the Stokes parameter measurement device are respectively used to adjust the linear polarization direction of the idle light passing through the first rubidium-87 atomic ensemble and the signal light passing through the second rubidium-87 atomic ensemble, and the elliptical polarization rate of the idle light passing through the first rubidium-87 atomic ensemble and the signal light passing through the second rubidium-87 atomic ensemble.

7. The detection device according to claim 4, characterized in that: The output ends of the first and second rubidium-85 atomic ensembles are respectively provided with a piezoelectric ceramic driver and a 1 / 2 wave plate for adjusting the phase and / or linear polarization direction of the first and second component signal lights; The 1 / 4 wave plate in the magnetometer is used to adjust the elliptical polarization rate of the third coherent light source and the fourth coherent light source respectively.

8. The detection device according to claim 6 or 7, characterized in that: The adjustments include: The first coherent light source and the first seed light are spaced at 0.3° to 0.4°; The second coherent light source and the second seed light cross and merge at a certain angle at the center of the second rubidium-85 atomic ensemble; The second coherent light source and the second seed light are spaced at 0.3° to 0.4°; The first component signal light and the first idler light are separated from the center of the first atomic ensemble at an angle of 0.6° to 0.8°; The second component signal light and the second idler light are distributed at equal angles on both sides of the second coherent light source 2; The second component signal light and the second idler light are separated from the center of the second atomic ensemble at an angle of 0.6° to 0.8°; The polarization direction of the first component idler light is perpendicular to the polarization direction of the second component idler light after passing through the first 1 / 2 wave plate; The phase of the first component idler light is consistent with the phase of the second component idler light after passing through the second piezoelectric ceramic driver 8; The polarization direction of the first component signal light after passing through the second 1 / 2 wave plate is perpendicular to the polarization direction of the second component signal light; The phase of the first component signal light after passing through the first piezoelectric ceramic driver is consistent with the phase of the second component signal light.

9. The detection device according to claim 6 or 7, characterized in that: The detection specifically includes: Step 1, injecting the frequency-modulated first coherent light source, the first seed light, the second coherent light source, the second seed light into the first rubidium-85 atomic ensemble and the second rubidium-85 atomic ensemble respectively to generate four-wave mixing, and generating two pairs of entangled light with entanglement characteristics, namely, the first component signal light, the first idler light, and the second component signal light, the second idler light; Step 2, combining the first idler light and the second idler light into idler light through a second polarization beam splitter; combining the first component signal light and the second component signal light into signal light through a second polarization beam splitter; the idler light and the signal light are a multi-dimensional polarization entangled light source; and modulating the polarization and compression direction thereof through a first piezoelectric ceramic driver and a second piezoelectric ceramic driver at the same time; Step 3, first injecting the polarization-modulated third coherent light source 3 and the fourth coherent light source into the first rubidium-87 atomic ensemble and the second rubidium-87 atomic ensemble for optical pumping; simulating the magnetic field to be measured by the Helmholtz coils around them; The method comprises the following steps: injecting the signal light and the idler light of the multidimensional polarization entangled light source into the first rubidium-87 atomic ensemble and the second rubidium-87 atomic ensemble respectively, coupling the magnetic field information to the Stokes parameter of the multidimensional polarization entangled light source through the atoms; injecting the signal light and the idler light into the Stokes parameter detection system after emission, detecting the Stokes parameter of the multidimensional polarization entangled light source, and analyzing to obtain the magnetic field information.

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