Three-photon atomic spectral line frequency-locking system for rubidium atom Rydberg microwave electric field meters

Abstract

This invention discloses a three-photon atomic spectral line frequency-locking system for a rubidium atom Rydberg microwave field meter, comprising a 780nm laser, a 1260nm laser, a 776nm laser, a saturated absorption spectroscopy detection system, an EIT detection system, an EIA detection system, a saturated absorption spectroscopy frequency-locking system, an EIT frequency-locking system, and an EIA frequency-locking system. This invention uses a three-photon excitation scheme instead of the traditional two-photon excitation scheme, significantly reducing the size of the laser used and ensuring stable output laser frequency and power. This invention employs a frequency-locking method combining SAS, EIT, and EIA spectra, which significantly improves the laser frequency-locking time compared to current PDH frequency-locking methods or laser self-operation frequency-locking methods. This invention uses a three-photon modulation method with a unified common modulation frequency for atomic spectral lines, effectively reducing the complexity of frequency-locking in the three-photon Rydberg system, making the method more widely applicable and practical.

Description

Technical Field

[0001] This invention relates to the fields of Rydberg atomic excitation technology, frequency locking technology, and microwave electric field meter technology, and in particular to a three-photon atomic spectral line frequency locking system for a rubidium atom Rydberg microwave electric field meter. Background Technology

[0002] Rydberg atoms are excited-state atoms in a high principal quantum number (n≥15) state. Due to their large atomic radius and large dipole moment, microwave detection technology based on Rydberg atoms has outstanding advantages such as ultra-wide detection spectrum, high sensitivity, and high detection accuracy. Improving the signal-to-noise ratio and detection accuracy in Rydberg atom-based microwave detection technology, expanding the diversity of Rydberg atom excitation schemes, increasing the integration of Rydberg atom microwave detection schemes, and expanding the application scenarios of Rydberg atom microwave detection technology are important aspects of the microwave detection field.

[0003] The three-light Rydberg atomic microwave electric field meter can achieve high-precision measurement of microwave electric fields. Its measurement accuracy can approach or even exceed the standard quantum limit, providing a precise measurement method for the field of quantum metrology. It helps to establish more accurate microwave electric field metrology standards, realize traceable measurement of microwave electric fields, and has significant application value in the military and communications fields.

[0004] Current Rydberg atomic excitation schemes mainly employ a two-light excitation method, using a long-wavelength red light as the probe and a short-wavelength blue light as the coupling light for excitation. All these schemes require frequency locking of the laser. Current methods primarily use atomic saturation spectroscopy for the first excitation light, but there are no good solutions for highly excited lasers, or hypercavity locking methods are used. These methods are mostly used in scientific research experimental platforms.

[0005] Early two-light Rydberg atomic excitation schemes suffered from drawbacks such as the high cost and large size of the short-wavelength lasers used, and the inability to maintain stable output laser frequency and power over long periods.

[0006] The three-light Rydberg atomic excitation scheme requires precise frequency locking of the three lights. Currently, the most common method for locking the probe light frequency in scientific research is SAS (Saturated Absorption Spectroscopy). Locking the frequencies of the coupling and modification lights often employs the PDH (Pound-Drever-Hall) method, or temporarily stabilizing the laser at a certain frequency point by allowing it to run freely. However, this method is only suitable for short-term scientific research and does not meet the practical needs of long-term operation of electric field meters in current industrial applications. Summary of the Invention

[0007] The purpose of this invention is to address the shortcomings of current frequency-locking schemes for three-light Rydberg electric field meter devices by providing a three-light atomic spectral line frequency-locking system for rubidium atomic Rydberg microwave electric field meters.

[0008] The present invention achieves the above objectives through the following technical means:

[0009] The three-photon atomic spectral line locking system for a rubidium atom Rydberg microwave electric field meter includes a 780nm laser, a 1260nm laser, a 776nm laser, an EIA detection system, and an EIA locking system. The 780nm laser output is split into a first 780nm laser, a third 780nm laser, and a fourth 780nm laser. The 776nm laser output is split into a first 776nm laser and a second 776nm laser.

[0010] The 1260nm laser output from the 1260nm laser, the second 776nm laser, and the fourth 780nm laser are input into the EIA detection system. The EIA detection system outputs a 780nm laser carrying the Rydberg state three-light EIA spectral signal of rubidium atoms. The EIA frequency locking system coherently demodulates the 780nm laser carrying the Rydberg state three-light EIA spectral signal of rubidium atoms and outputs a third error signal to the PID controller of the 1260nm laser. The PID controller of the 1260nm laser locks the laser frequency output by the 1260nm laser to the Rydberg state three-light EIA spectrum of rubidium atoms according to the third error signal.

[0011] As described above, the EIA detection system includes a third half-wave plate, a fourth half-wave plate, a third polarizing beam splitter, a third rubidium atom gas cell, a fourth polarizing beam splitter, a second reflecting mirror, and a first photoelectric probe;

[0012] The second 776nm laser passes sequentially through the fourth half-wave plate and the fourth polarizing beam splitter before entering the third rubidium atom gas chamber;

[0013] The fourth 780nm laser passes sequentially through the third half-wave plate and the third polarizing beam splitter before entering the third rubidium atom gas chamber;

[0014] The 1260nm laser output from the 1260nm laser passes through the second reflecting mirror and the third polarizing beam splitter in sequence before entering the third rubidium atom gas chamber;

[0015] A 1260nm laser, a second 776nm laser, and a fourth 780nm laser are input into the third rubidium atom gas chamber to obtain a seventh 780nm laser. The seventh 780nm laser is a 780nm laser carrying the Rydberg state three-light EIA spectral signal of rubidium atoms. After passing through the fourth polarization beam splitter, the seventh 780nm laser is input into the first photodetector. The first photodetector detects the seventh 780nm laser and converts it into a third electrical signal.

[0016] As described above, the EIA frequency locking system includes a signal generator and a first mixer. The signal generator outputs a sine wave signal to the first mixer, and the first photodetector outputs a third electrical signal to the first mixer. The sine wave signal and the third electrical signal are mixed by the first mixer to obtain a third error signal.

[0017] It also includes a saturated absorption spectroscopy detection system and a saturated absorption spectroscopy frequency locking system. The first 780nm laser is input into the saturated absorption spectroscopy detection system, which outputs a 780nm laser carrying the D1 line saturated absorption spectral signal of rubidium atoms. The saturated absorption spectroscopy frequency locking system performs coherent demodulation on the 780nm laser carrying the D1 line saturated absorption spectral signal of rubidium atoms and outputs a first error signal to the PID controller of the 780nm laser. The PID controller of the 780nm laser locks the laser frequency output by the 780nm laser to the D1 line saturated absorption spectrum of rubidium atoms according to the first error signal.

[0018] As described above, the saturated absorption spectral detection system includes an electro-optic modulator, a first beam splitter, a first half-wave plate, a first polarizing beam splitter, a first rubidium atom gas cell, a quarter-wave plate, a first reflecting mirror, and a second photodetector. The 780nm laser output from the 780nm laser is modulated by the electro-optic modulator to output 780nm modulated light. The 780nm modulated light is then split by the first beam splitter into a first 780nm laser and a second 780nm laser. The first 780nm laser passes sequentially through the first half-wave plate, the first polarizing beam splitter, the first rubidium atom gas cell, the quarter-wave plate, and the first reflecting mirror. After being reflected by the first reflecting mirror, it passes sequentially through the quarter-wave plate and the first rubidium atom gas cell to obtain a fifth 780nm laser. The fifth 780nm laser is a 780nm laser carrying the D1 line saturated absorption spectral signal. After passing through the first polarizing beam splitter, the fifth 780nm laser is input to the second photodetector. The second photodetector detects the fifth 780nm laser and converts it into a first electrical signal.

[0019] As described above, the saturated absorption spectroscopy frequency locking system includes a signal generator and a second mixer. The signal generator outputs a sinusoidal signal to the second mixer, and the second photodetector outputs a first electrical signal to the second mixer. The sinusoidal signal and the first electrical signal are mixed by the second mixer to obtain a first error signal.

[0020] It also includes an EIT detection system and an EIA frequency locking system. A first 776nm laser and a third 780nm laser are input into the EIT detection system. The EIT detection system outputs a 780nm laser carrying the 5D state two-light EIT spectrum signal of rubidium atoms. The EIT frequency locking system performs coherent demodulation on the 780nm laser carrying the 5D state two-light EIT spectrum signal of rubidium atoms and outputs a second error signal to the PID controller of the 776nm laser. The PID controller of the 776nm laser locks the laser frequency output by the 776nm laser to the 5D state two-light EIT spectrum of rubidium atoms according to the second error signal.

[0021] As described above, the EIT detection system includes a third beam splitter, a second polarizing beam splitter, a second half-wave plate, a second rubidium atom gas cell, and a second beam splitter.

[0022] The 776nm laser output from the 776nm laser is split into a first 776nm laser and a second 776nm laser by the third beam splitter. The first 776nm laser passes through the second polarizing beam splitter and the second half-wave plate in sequence and is input into the second rubidium atom gas cell.

[0023] The second 780nm laser is sequentially split into a third 780nm laser and a fourth 780nm laser by the second beam splitter. The third 780nm laser is then input into the second rubidium atom gas chamber.

[0024] The first 776nm laser and the third 780nm laser are input into the second rubidium atom gas cell to obtain the sixth 780nm laser. The sixth 780nm laser is a 780nm laser carrying the 5D state two-light EIT spectral signal of rubidium atoms. The sixth 780nm laser passes through the second half-wave plate and the second polarizing beam splitter in sequence and is then input into the third photodetector. The third photodetector detects the sixth 780nm laser and converts it into a second electrical signal.

[0025] As described above, the EIT frequency locking system includes a signal generator and a third mixer. The signal generator outputs a sine wave signal to the third mixer, and the third photodetector outputs a second electrical signal to the third mixer. The sine wave signal and the second electrical signal are mixed by the third mixer to obtain a second error signal.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] (1) The present invention adopts a three-photon excitation scheme to replace the traditional two-photon excitation scheme, which greatly reduces the size of the laser used and the output laser frequency and power are stable and controllable.

[0028] (2) The present invention adopts a frequency locking method that combines SAS spectrum, EIT spectrum, and EIA spectrum, which significantly improves the laser frequency locking time compared with the current PDH frequency locking method or laser self-running frequency locking method.

[0029] (3) The present invention adopts a three-light modulation method of atomic spectral lines with a unified common modulation frequency, which fully reduces the frequency locking complexity of the three-light Rydberg system, making the method of the present invention more widely applicable.

[0030] In summary, based on the numerous characteristics of Rydberg atoms and laboratory results, this invention proposes and implements a method for long-term locking of the three optical frequencies of atomic spectral lines using a unified common modulation frequency. This method features long-term stable operation, ease of use, large-scale production capability, and wide applicability in important fields such as weak microwave field detection and communication. It overcomes the shortcomings of the original scheme, such as large device size, unstable laser power, and inability to lock frequencies and operate for extended periods. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the system structure of the present invention;

[0032] Figure labels and corresponding component names:

[0033] 1-1260nm laser; 2-780nm laser; 3-776nm laser; 4-First beam splitter; 5-Second beam splitter; 6-Third beam splitter; 7-First half-wave plate; 8-Second half-wave plate; 9-Third half-wave plate; 10-Fourth half-wave plate; 11-First polarizing beam splitter; 12-Second polarizing beam splitter; 13-Third polarizing beam splitter; 14-Fourth polarizing beam splitter; 15-First rubidium atom gas cell; 16-Second rubidium atom gas cell; 17-Third rubidium atom gas cell; 18-Quarter-wave plate; 19-First reflecting mirror; 20-Second reflecting mirror; 21-First photodetector; 22-Second photodetector; 23-Third photodetector; 24-First mixer; 25-Second mixer; 26-Third mixer; 27-Signal generator; 28-Electro-optic modulator. Detailed Implementation Plan

[0034] To facilitate understanding and implementation of the present invention by those skilled in the art, the present invention will be further described in detail below with reference to embodiments. It should be understood that the embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0035] Example 1:

[0036] like Figure 1As shown, the three-photon atomic spectral line locking system for a rubidium atom Rydberg microwave electric field meter includes a 780nm laser 2, a 1260nm laser 1, a 776nm laser 3, a saturated absorption spectroscopy detection system, an EIT detection system, an EIA detection system, a saturated absorption spectroscopy locking system, an EIT locking system, and an EIA locking system.

[0037] The 780nm laser output from the 780nm laser 2 is split into a first 780nm laser, a third 780nm laser, and a fourth 780nm laser. The first 780nm laser is input into the saturated absorption spectroscopy detection system, which outputs a 780nm laser carrying the D1 line saturated absorption spectral signal of rubidium atoms. The saturated absorption spectroscopy frequency locking system performs coherent demodulation on the 780nm laser carrying the D1 line saturated absorption spectral signal of rubidium atoms and outputs a first error signal to the PID controller of the 780nm laser 2. The PID controller of the 780nm laser 2 locks the laser frequency output by the 780nm laser 2 to the D1 line saturated absorption spectrum of rubidium atoms according to the first error signal.

[0038] The 776nm laser 3 outputs a split beam consisting of a first 776nm laser and a second 776nm laser. The first 776nm laser and the third 780nm laser are input into the EIT detection system. The EIT detection system outputs a 780nm laser carrying the 5D state two-light EIT spectral signal of rubidium atoms. The EIT frequency locking system performs coherent demodulation on the 780nm laser carrying the 5D state two-light EIT spectral signal of rubidium atoms and outputs a second error signal to the PID controller of the 776nm laser 3. The PID controller of the 776nm laser 3 locks the laser frequency output by the 776nm laser 3 to the 5D state two-light EIT spectrum of rubidium atoms according to the second error signal.

[0039] The 1260nm laser output from 1260nm laser 1, along with the second 776nm laser and the fourth 780nm laser, are input into the EIA detection system. The EIA detection system outputs a 780nm laser carrying the Rydberg state three-light EIA spectral signal of rubidium atoms. The EIA frequency locking system coherently demodulates the 780nm laser carrying the Rydberg state three-light EIA spectral signal of rubidium atoms and outputs a third error signal to the PID controller of 1260nm laser 1. The PID controller of 1260nm laser 1 locks the laser frequency output by 1260nm laser 1 to the Rydberg state three-light EIA spectrum of rubidium atoms based on the third error signal.

[0040] The saturated absorption spectroscopy detection system includes an electro-optic modulator 28, a first beam splitter 4, a first half-wave plate 7, a first polarizing beam splitter 11, a first rubidium atom gas cell 15, a quarter-wave plate 18, a first reflecting mirror 19, and a second photodetector 22. The 780nm laser output from the 780nm laser 2 is modulated by the electro-optic modulator 28 to output 780nm modulated light. This 780nm modulated light is then split by the first beam splitter 4 into a first 780nm laser (the laser emitted by the first beam splitter 4, whose propagation direction changes by 90° from its original direction) and a second 780nm laser (the laser transmitted through and reflected by the first beam splitter 4, propagating along its original direction). The first 780nm laser is input to the first half-wave plate 7. The 780nm laser light is converted into first polarized light (with a half-phase phase difference relative to the first 780nm laser light) by the first half-wave plate 7. The first polarized light light is transmitted through the first polarizing beam splitter 11, the first rubidium atom gas cell 15, and the quarter-wave plate 18. After being reflected by the first reflecting mirror 19, it passes through the quarter-wave plate 18 and the first rubidium atom gas cell 15 again to obtain a 780nm laser light carrying the D1 line saturated absorption spectrum signal, which is denoted as the fifth 780nm laser light (at this time, the phase difference relative to the first 780nm laser light changes from half-phase to one-phase). The fifth 780nm laser light is reflected by the first polarizing beam splitter 11 and enters the second photodetector 22. The second photodetector 22 detects the fifth 780nm laser light and converts it into a first electrical signal.

[0041] In one possible implementation, the 780nm laser 2 outputs 780nm laser light to the electro-optic modulator 28, and the electro-optic modulator 28 outputs 780nm modulated light. The first beam splitter 4 is placed on the same vertical axis as the electro-optic modulator 28, and the incident surface of the first beam splitter 4 faces the 780nm modulated light output by the electro-optic modulator 28. The adjacent side of the incident surface of the first beam splitter 4 faces the first half-wave plate 7. The first half-wave plate 7, the first polarizing beam splitter 11, the first rubidium atom gas cell 15, the quarter-wave plate 18, and the first reflector 19 are placed on the same horizontal axis in sequence. The optical axes of the quarter-wave plate 18 and the first reflector 19 are both coincident with the first half-wave plate 7.

[0042] The EIT detection system includes a third beam splitter 6, a second polarizing beam splitter 12, a second half-wave plate 8, a second rubidium atom gas cell 16, and a second beam splitter 5;

[0043] The 776nm laser output from the 776nm laser 3 is split into a first 776nm laser (the laser reflected by the third beam splitter 6, whose propagation direction changes by 90° from the original propagation direction) and a second 776nm laser (the laser transmitted through the third beam splitter 6 and reflected along the original propagation direction). The first 776nm laser is transmitted through the second polarizing beam splitter 12 and the second half-wave plate 8 and enters the second rubidium atom gas chamber 16.

[0044] The second 780nm laser is input into the second beam splitter 5, which splits the laser into a third 780nm laser (the laser reflected by the second beam splitter 5, whose propagation direction changes by 90° from the original propagation direction) and a fourth 780nm laser (the laser transmitted through the second beam splitter 5 and reflected, which propagates along the original propagation direction). The third 780nm laser is input into the second rubidium atom gas chamber 16.

[0045] The first 776nm laser and the third 780nm laser are input into the second rubidium atom gas chamber 16. The 780nm modulated light and the 776nm laser interact with the atoms in the second rubidium atom gas chamber 16 to produce the EIT phenomenon, resulting in a 780nm laser carrying the 5D state two-light EIT spectral signal of rubidium atoms, which is denoted as the sixth 780nm laser. The sixth 780nm laser passes sequentially through the second half-wave plate 8 and the second polarizing beam splitter 12, and is reflected by the second polarizing beam splitter 12 to the third photodetector 23. The third photodetector 23 detects the sixth 780nm laser and converts it into a second electrical signal.

[0046] The second half-wave plate 8 and the second polarizing beam splitter 12 are used to change the phase of the first 776nm laser, the third 780nm laser, and the sixth 780nm laser, to prevent the first 776nm light from being falsely detected by the third photoelectric probe 23, and to ensure that the sixth 780nm laser is accurately detected.

[0047] In one possible implementation, the second beam splitter 5 is placed along the same longitudinal axis as the first beam splitter 4, with the incident surface of the second beam splitter 5 facing the transmitted light exit surface of the first beam splitter 4. The second beam splitter 5, the second rubidium atom gas cell 16, the second half-wave plate 8, the second polarizing beam splitter 12, and the third beam splitter 6 are placed along the same transverse axis. The optical axis of the second half-wave plate 8 and the transmitted light optical axis of the second polarizing beam splitter 12 both coincide with the reflected light optical axis of the second beam splitter 5. The reflected light of the second polarizing beam splitter 12 is directly opposite the third photodetector 23.

[0048] The EIA detection system includes a third half-wave plate 9, a fourth half-wave plate 10, a third polarizing beam splitter 13, a third rubidium atom gas cell 17, a fourth polarizing beam splitter 14, a second reflector 20, and a first photoelectric probe 21;

[0049] The second 776nm laser passes sequentially through the fourth half-wave plate 10 and the fourth polarizing beam splitter 14, and is reflected by the fourth polarizing beam splitter 14 into the third rubidium atom gas chamber 17.

[0050] The fourth 780nm laser passes sequentially through the third half-wave plate 9 and the third polarizing beam splitter 13;

[0051] The 1260nm laser output from the 1260nm laser 1 is reflected by the second mirror 20 and enters the third polarization beam splitter 13. The combined beam of the laser beam and the fourth 780nm laser entering the third polarization beam splitter 13 enters the third rubidium atom gas chamber 17.

[0052] The combined beam and the second 776nm laser enter the third rubidium atom gas chamber 17 and interact with the atoms to obtain a 780nm laser carrying the Rydberg state three-light EIA spectral signal of rubidium atoms, which is denoted as the seventh 780nm laser. The seventh 780nm laser is transmitted through the fourth polarizing beam splitter 14 and enters the first photodetector 21. The first photodetector 21 detects the seventh 780nm laser and converts it into a third electrical signal.

[0053] In one possible implementation, the third beam splitter 6 is placed along the same horizontal axis as the second beam splitter 5, with the incident surface of the third beam splitter 6 facing the transmitted light exit surface of the second beam splitter 5. The second reflecting mirror 20, the third polarizing beam splitter 13, the fourth polarizing beam splitter 14, and the third rubidium atom gas cell 17 are also placed along the same horizontal axis. The third half-wave plate 9 is placed between the second beam splitter 5 and the third polarizing beam splitter 13, with its incident surface facing the transmitted light from the second beam splitter 5. The fourth half-wave plate 10 is placed between the third beam splitter 6 and the fourth polarizing beam splitter 14, with its incident surface facing the transmitted light from the third beam splitter 6. The normal direction of the second reflecting mirror 20 forms a 45° angle with the output direction of the 1260nm laser 1. The normal direction of the second reflecting mirror 20 is perpendicular to the beam splitting direction of the third polarizing beam splitter 13 and parallel to the beam splitting direction of the fourth polarizing beam splitter 14. The horizontally placed third rubidium atom gas cell 17 has its laser incident and exit surfaces directly opposite the transmitted light from the third polarizing beam splitter 13 and the incident surface from the fourth polarizing beam splitter 14, respectively. The transmitted light from the fourth polarizing beam splitter 14 is directly opposite the first photodetector 21.

[0054] The saturated absorption spectroscopy frequency locking system includes a signal generator 27 and a second mixer 25. The signal generator 27 outputs a sinusoidal signal to the second mixer 25. The two input terminals of the second mixer 25 are connected to the output terminals of the signal generator 27 and the output terminals of the second photodetector 22. The second photodetector 22 outputs a first electrical signal to the second mixer 25. The sinusoidal signal and the first electrical signal are mixed (multiplied) by the second mixer 25, i.e., coherent demodulation is performed to obtain a first error signal (i.e., a dispersive signal with a center of 0 and positive and negative linear changes on both sides of the center, reflecting the degree of deviation of the 780nm laser). The PID controller of the 780nm laser 2 adjusts the driver of the 780nm laser 2 according to the first error signal to pull the laser frequency output by the 780nm laser 2 back to the locking point, thereby locking the laser frequency output by the 780nm laser 2 to the D1 line saturated absorption spectrum of rubidium atoms.

[0055] The EIT frequency locking system includes a signal generator 27 and a third mixer 26. The signal generator 27 outputs a sinusoidal signal to the third mixer 26. The two input terminals of the third mixer 26 are connected to the output terminal of the signal generator 27 and the output terminal of the third photodetector 23. The third photodetector 23 outputs a second electrical signal to the third mixer 26. The sinusoidal signal and the second electrical signal are mixed (multiplied) by the third mixer 26, i.e., coherent demodulation is performed to obtain a second error signal (reflecting the degree of deviation of the 776nm laser). The PID controller of the 776nm laser 3 adjusts the driver of the 776nm laser 3 according to the second error signal to pull the laser frequency output by the 776nm laser 3 back to the locking point, thereby locking the laser frequency output by the 776nm laser 3 to the 5D state two-light EIT spectrum of rubidium atoms.

[0056] The EIA frequency locking system includes a signal generator 27 and a first mixer 24. The signal generator 27 outputs a sinusoidal signal to the first mixer 24. The two input terminals of the first mixer 24 are connected to the output terminal of the signal generator 27 and the output terminal of the first photodetector 21. The first photodetector 21 outputs a third electrical signal to the first mixer 24. The sinusoidal signal and the third electrical signal are mixed (multiplied) by the first mixer 24, i.e., coherent demodulation is performed to obtain a third error signal (reflecting the degree of deviation of the 1260nm laser). The PID controller of the 1260nm laser 1 adjusts the driver of the 1260nm laser 1 according to the third error signal to pull the laser frequency output by the 1260nm laser 1 back to the locking point, thereby locking the laser frequency output by the 1260nm laser 1 to the Rydberg state three-photon EIA spectrum of rubidium atoms.

[0057] The specific examples described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific examples or use similar methods to replace them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A three optical atom spectroscopic frequency locking system for a rubidium atom Rydberg microwave electric field meter, comprising a 780 nm laser (2), a 776 nm laser (3), a saturated absorption spectroscopy detection system, an EIT detection system, a saturated absorption spectroscopy frequency locking system, and an EIT frequency locking system, characterized in that, Also including 1260nm laser (1), EIA detection system, and EIA frequency locking system; The 780nm laser (2) outputs 780nm laser, which is split into first 780nm laser, third 780nm laser, and fourth 780nm laser, the first 780nm laser is input into the saturated absorption spectrum detection system, the saturated absorption spectrum detection system outputs 780nm laser carrying D1 line saturated absorption spectrum signal of rubidium atom, the saturated absorption spectrum frequency locking system coherently demodulates the 780nm laser carrying D1 line saturated absorption spectrum signal of rubidium atom, outputs first error signal to the PID controller of the 780nm laser (2), and the PID controller of the 780nm laser (2) locks the laser frequency output by the 780nm laser (2) on the D1 line saturated absorption spectrum of rubidium atom according to the first error signal; The 776nm laser (3) outputs first 776nm laser and second 776nm laser, the first 776nm laser and the third 780nm laser are input into the EIT detection system, the EIT detection system outputs 780nm laser carrying 5D state two-light EIT spectrum signal of rubidium atom, the EIT frequency locking system coherently demodulates the 780nm laser carrying 5D state two-light EIT spectrum signal of rubidium atom, outputs second error signal to the PID controller of the 776nm laser (3), and the PID controller of the 776nm laser (3) locks the laser frequency output by the 776nm laser (3) on the 5D state two-light EIT spectrum of rubidium atom according to the second error signal; The 1260nm laser (1) outputs 1260nm laser, the 1260nm laser, the second 776nm laser, and the fourth 780nm laser are input into the EIA detection system, the EIA detection system outputs 780nm laser carrying Rydberg state three-light EIA spectrum signal of rubidium atom, the EIA frequency locking system coherently demodulates the 780nm laser carrying Rydberg state three-light EIA spectrum signal of rubidium atom, outputs third error signal to the PID controller of the 1260nm laser (1), and the PID controller of the 1260nm laser (1) locks the laser frequency output by the 1260nm laser (1) on the Rydberg state three-light EIA spectrum of rubidium atom according to the third error signal; The EIA frequency locking system includes signal generator (27) and first frequency mixer (24), the signal generator (27) outputs sinusoidal signal to the first frequency mixer (24), the first photoelectric probe (21) outputs third electric signal to the first frequency mixer (24), and the sinusoidal signal and the third electric signal are mixed by the first frequency mixer (24) to obtain the third error signal; The saturated absorption frequency locking system comprises a signal generator (27) and a second frequency mixer (25), the signal generator (27) outputs a sinusoidal signal to the second frequency mixer (25), the second photoelectric probe (22) outputs a first electric signal to the second frequency mixer (25), and the sinusoidal signal and the first electric signal are mixed by the second frequency mixer (25) to obtain a first error signal; The EIT frequency locking system comprises a signal generator (27) and a third frequency mixer (26), the signal generator (27) outputs a sinusoidal signal to the third frequency mixer (26), the third photoelectric probe (23) outputs a second electric signal to the third frequency mixer (26), and the sinusoidal signal and the second electric signal are mixed by the third frequency mixer (26) to obtain a second error signal.

2. The three optical atom spectral line frequency locking system for a rubidium atom Rydberg microwave electric field meter according to claim 1, characterized in that, The EIA detection system comprises a third half-wave plate (9), a fourth half-wave plate (10), a third polarizing beam splitter (13), a third rubidium atomic cell (17), a fourth polarizing beam splitter (14), a second reflector (20), and a first photoelectric probe (21); The second 776nm laser passes through the fourth half-wave plate (10) and the fourth polarizing beam splitter (14) in sequence and then enters the third rubidium atomic cell (17); The fourth 780nm laser passes through the third half-wave plate (9) and the third polarizing beam splitter (13) in sequence and then enters the third rubidium atomic cell (17); The 1260nm laser output by the 1260nm laser (1) passes through the second reflector (20) and the third polarizing beam splitter (13) in sequence and then enters the third rubidium atomic cell (17); The 1260nm laser, the second 776nm laser, and the fourth 780nm laser are input into the third rubidium atomic cell (17) to obtain a seventh 780nm laser, the seventh 780nm laser is a 780nm laser carrying a Rydberg state three-light EIA spectrum signal of rubidium atoms, and the seventh 780nm laser is input into the first photoelectric probe (21) after passing through the fourth polarizing beam splitter (14), the first photoelectric probe (21) detects the seventh 780nm laser and converts it into a third electric signal.

3. The three optical atom spectral line frequency locking system for a rubidium atom Rydberg microwave electric field meter according to claim 1, characterized in that, The saturated absorption spectrum detection system comprises an electro-optical modulator (28), a first beam splitter (4), a first half-wave plate (7), a first polarized light splitter (11), a first rubidium atom gas chamber (15), a quarter-wave plate (18), a first mirror (19), and a second photoelectric probe (22), 780nm laser output by a 780nm laser (2) is modulated by the electro-optical modulator (28) to output 780nm modulated light, the 780nm modulated light is split into first 780nm light and second 780nm light by the first beam splitter (4), the first 780nm light passes through the first half-wave plate (7), the first polarized light splitter (11), the first rubidium atom gas chamber (15), the quarter-wave plate (18), and the first mirror (19) in sequence, is reflected by the first mirror (19), and then passes through the quarter-wave plate (18) and the first rubidium atom gas chamber (15) in sequence to obtain fifth 780nm light, the fifth 780nm light is 780nm light carrying a D1 line saturated absorption spectrum signal, and the fifth 780nm light is input to the second photoelectric probe (22) after passing through the first polarized light splitter (11), the second photoelectric probe (22) detects the fifth 780nm light and converts it into a first electric signal.

4. The three optical atom spectral line frequency locking system for a rubidium atom Rydberg microwave electric field meter according to claim 1, characterized in that, The EIT detection system comprises a third beam splitter (6), a second polarized light splitter (12), a second half-wave plate (8), a second rubidium atom gas chamber (16), and a second beam splitter (5); 776nm laser output by a 776nm laser (3) is split into first 776nm light and second 776nm light by the third beam splitter (6), the first 776nm light is input to the second rubidium atom gas chamber (16) after passing through the second polarized light splitter (12) and the second half-wave plate (8) in sequence; The second 780nm light is split into third 780nm light and fourth 780nm light by the second beam splitter (5) in sequence, and the third 780nm light is input to the second rubidium atom gas chamber (16); The first 776nm light and the third 780nm light are input to the second rubidium atom gas chamber (16) to obtain sixth 780nm light, the sixth 780nm light is 780nm light carrying a 5D state two-light EIT spectrum signal of a rubidium atom, and the sixth 780nm light is input to a third photoelectric probe (23) after passing through the second half-wave plate (8) and the second polarized light splitter (12) in sequence, the third photoelectric probe (23) detects the sixth 780nm light and converts it into a second electric signal.

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