A microwave measurement high-sensitivity readout system for a rydberg atom pumping system

Abstract

The present application relates to a kind of microwave measurement high sensitivity readout system of Rydberg atom pumping system, belong to microwave measurement technical field.The system utilizes the technical means of optical amplification, combines balanced homodyne detection and balanced heterodyne detection technology, by controlling the frequency of local oscillator light I and local oscillator light III, the sensitivity of microwave measurement system is improved and the readout of phase information is realized, greatly simplifies the engineering difficulty and control difficulty of system, provides new technical method for the measurement of high sensitivity microwave signal and the readout of microwave signal phase information.

Description

Technical Field

[0001] This invention belongs to the field of microwave measurement technology and relates to a high-sensitivity readout system for microwave measurement of a Rydberg atomic pump system. Background Technology

[0002] Rydberg atoms are atoms whose outer electrons are pumped to a highly excited state using laser manipulation. Typically, this is achieved through a two-photon process, pumping the atom to an energy level with a principal quantum number n greater than 20. At this level, the shell electron is relatively far from the nucleus, resulting in a large electric dipole moment between the nucleus and the electron. Therefore, Rydberg atoms exhibit extremely high sensitivity to frequency-matched microwave electric fields. By controlling the change in the principal quantum number of a Rydberg atom, microwave measurement frequencies can be achieved from kHz to THz. Compared to traditional microwave receiving systems, Rydberg atoms are not limited by microwave wavelength during coupling with microwave signals, thus possessing enormous application potential in the field of microwave measurement.

[0003] By utilizing the high sensitivity of Rydberg atoms to microwave signals, microwave signals can be measured and the information carried by microwaves can be demodulated and acquired. However, all current data readout schemes use detectors to directly detect optical signals. Since the electrical detection system amplifies both the signal and noise, the data readout system has low sensitivity and cannot read out the phase information in the optical signal. Summary of the Invention

[0004] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a microwave measurement high-sensitivity readout system for Rydberg atomic pump systems.

[0005] The solution of the present invention is:

[0006] A microwave measurement high-sensitivity readout system for a Rydberg atom pump system includes: beam splitter prism I, beam splitter prism II, beam combiner prism I, beam combiner prism II, beam combiner prism III, acousto-optic modulator I, acousto-optic modulator II, single-mode fiber I, single-mode fiber II, single-mode fiber III, plane high-reflection mirror I, plane high-reflection mirror II, plane high-reflection mirror III, plane high-reflection mirror IV, pump light balanced detector, reference light balanced detector, and probe light balanced detector;

[0007] The local oscillating light is split into two paths after passing through beam splitter I. One path, as the local oscillating light I, is reflected to acousto-optic modulator I for acousto-optic modulation. The modulated optical signal is coupled into single-mode fiber I and incident on plane high-reflection mirror II. The other path, as the transmitted light I, is transmitted to beam splitter II and processed into two optical paths. One path, as the local oscillating light II, is coupled into single-mode fiber II and incident on plane high-reflection mirror III. The other path, as the transmitted light II, is transmitted to plane high-reflection mirror I and reflected by plane high-reflection mirror I to obtain local oscillating light III. Local oscillating light III is coupled into single-mode fiber III and incident on plane high-reflection mirror IV.

[0008] The single-mode fiber I is tuned so that the local oscillator I and the pump light have the same spatial mode. The local oscillator I reflected by the plane high-reflection mirror II and the pump light emitted from the Rydberg atomic pump system are combined and interfered at the beam combining prism I. The local oscillator I performs balanced heterodyne amplification on the pump light. The interference signal is received by the pump light balanced detector and the pump photoelectric signal is output.

[0009] The single-mode fiber II is tuned to make the spatial modes of the local oscillator II and the reference light the same. The local oscillator II reflected by the plane high-reflection mirror III and the reference light emitted from the Rydberg atomic pump system are combined and interfered at the beam combining prism II. The local oscillator II performs balanced zero-beat amplification on the probe light. The interference signal is received by the reference light balanced detector and the reference photoelectric signal is output.

[0010] The single-mode fiber III is tuned so that the local oscillator III and the probe light have the same spatial mode. The local oscillator III emitted by the plane high-reflection mirror IV and the probe light emitted by the Rydberg atomic pump system are combined and interfered at the beam combining prism III. The local oscillator III performs balanced zero-beat amplification on the probe light. The interference signal is received by the probe light balanced detector and outputs the probe photoelectric signal.

[0011] Preferably, an electrical signal receiving device is used to receive a detection photoelectric signal, a reference photoelectric signal, and a pump photoelectric signal respectively. The reference photoelectric signal is subtracted from the detection photoelectric signal, and a noise reduction operation is performed to obtain microwave intensity information. The reference photoelectric signal is subtracted from the pump photoelectric signal, and a noise reduction operation is performed to obtain microwave phase information.

[0012] Preferably, the Rydberg atomic pumping system comprises a first laser, a second laser, a glass gas chamber containing alkali metal atoms, a heating plate, a first beam-splitting prism, a first acousto-optic modulator, a second acousto-optic modulator, a second beam-splitting prism, a first plane high-reflection mirror, a second plane high-reflection mirror, a third plane high-reflection mirror, a fourth plane high-reflection mirror, a fifth plane high-reflection mirror, a piezoelectric ceramic high-reflection mirror, a first long-wavelength lens, a second long-wavelength lens, a phase-locked balanced detector, a third beam-splitting prism, a first electro-optic modulator, a second electro-optic modulator, an optical trash can, a phase-locked laser, a fourth beam-splitting prism, a fifth beam-splitting prism, and a first beam-combining prism.

[0013] A glass gas chamber containing alkali metal atoms is located between two heating plates. The heating plates are energized to heat the atomic gas chamber. A first laser emits a continuous laser beam, which is split into two beams by a first beam-splitting prism. One beam is transmitted through the first beam-splitting prism and then frequency-shifted by a first acousto-optic modulator to be used as a probe beam. The other beam is split into two beams again by a second beam-splitting prism. One beam is reflected by the second beam-splitting prism and used directly as a reference beam. The other beam is split into two beams again by a fifth beam-splitting prism. One beam is reflected by the fifth beam-splitting prism and then frequency-shifted by a second acousto-optic modulator to be used as a pump beam. The other beam is incident on beam-splitting prism I as a local oscillation beam.

[0014] The probe beam, pump beam, and reference beam are three parallel laser beams. They are reflected by the first planar high-reflection mirror and the piezoelectric ceramic high-reflection mirror into three beams parallel to the heating plate. After being transmitted through the first long-wavelength lens, they enter the glass gas chamber from one side.

[0015] The phase-locked laser emits a continuous phase-locked laser, which is split into two beams by a fourth beam-splitting prism. One of the phase-locked laser beams travels the same path as the probe beam in space. After being reflected by a first plane high-reflection mirror and a piezoelectric ceramic high-reflection mirror, it is parallel to the heating plate and enters the glass gas chamber from one side. It passes through the glass gas chamber and is incident on a third plane high-reflection mirror. After being reflected by the third plane high-reflection mirror, it is combined with another phase-locked laser beam that has passed through a fourth plane high-reflection mirror and a first beam-combining prism in sequence to beat the frequency. The beat frequency signal is received by a phase-locked balanced detector.

[0016] The second laser emits a continuous laser beam, which is split into two beams by a third beam-splitting prism. One beam is transmitted through the third beam-splitting prism and reflected by a second high-reflection mirror. After being modulated by a second electro-optic modulator, it is used as the second coupling beam. The other beam is reflected by the third beam-splitting prism and incident on a fifth high-reflection mirror. After being reflected by the fifth high-reflection mirror, it is modulated by the second electro-optic modulator and used as the second coupling beam. The first and second coupling beams are reflected by a second long-wavelength lens and enter the glass gas cell from the other side. The first coupling beam coincides with the probe beam, and the second coupling beam coincides with the pump beam. After interacting with atoms, the first and second coupling beams are reflected by a first long-wavelength lens and received by an optical garbage bin.

[0017] The probe light, pump light, and reference light are emitted from a glass gas cell containing alkali metal atoms.

[0018] Preferably, the optical power of local oscillator I, local oscillator II, and local oscillator III is much greater than the optical power of pump light, reference light, and probe light.

[0019] Preferably, the probe light and the local oscillator III have the same frequency.

[0020] Preferably, the reference light and the local oscillator II have the same frequency.

[0021] Preferably, the acousto-optic modulator I is controlled to change the frequency detuning of the local oscillator I relative to the pump light frequency, so that there is a frequency difference between the pump light and the local oscillator I.

[0022] Preferably, the frequency of the first laser is locked to the resonance frequency of the transition from the ground state energy level to the excited state energy level of the atom.

[0023] Preferably, the frequency of the second laser is locked to the resonance frequency of the transition from the excited state energy level to the Rydberg state energy level of the atom.

[0024] The advantages of this invention compared to the prior art are:

[0025] This invention designs a high-sensitivity readout system for microwave measurement of a Rydberg atomic pump system. By utilizing optical amplification techniques combined with balanced beat detection and balanced heterodyne detection, and by manipulating the frequencies of local oscillator I and local oscillator III, the sensitivity of the microwave measurement system and the readout of phase information are improved. This greatly simplifies the engineering and control of the system, providing a new technology and method for the measurement of high-sensitivity microwave signals and the readout of phase information of microwave signals. Attached Figure Description

[0026] Figure 1 A schematic diagram of the Reedburg atomic pump system;

[0027] Figure 2This is a schematic diagram of the high-sensitivity readout system of the present invention;

[0028] Figure 3 This is a schematic diagram of the energy level structure of alkali metal atoms. Detailed Implementation

[0029] The invention will now be further described with reference to the accompanying drawings.

[0030] This invention relates to a high-sensitivity microwave readout system for Rydberg atomic pump systems. The Rydberg atomic pump system is as follows: Figure 1 As shown, the Rydberg atomic pumping system includes: an alkali metal atom gas chamber, a first laser, a second laser, a phase-locked laser, beam splitters 1, 2, 3, 4, and 5, a beam combiner 1, an acousto-optic modulator 1 and 2, an alkali metal atom gas chamber, a heating plate, plane high-reflection mirrors 1, 2, 3, 4, and 5, a piezoelectric ceramic high-reflection mirror, long-wavelength lens 1 and 2, an optical trash can, an electro-optic modulator, a phase-locked balanced detector, and a heating plate. A microwave measurement high-sensitivity readout system is also shown. Figure 2 As shown, it includes: beam splitter prism I, beam splitter prism II, beam combiner prism I, beam combiner prism II, beam combiner prism III, acousto-optic modulator I, acousto-optic modulator II, single-mode fiber I, single-mode fiber II, single-mode fiber III, plane high-reflection mirror I, plane high-reflection mirror II, plane high-reflection mirror III, plane high-reflection mirror IV, pump light balance detector, reference light balance detector, and probe light balance detector.

[0031] The atomic gas chamber is enclosed in the middle of a heating plate, which is used to increase the thermal motion of atoms, thereby increasing the atomic collision rate and manipulating the relative phase of the pump light and probe light to achieve high-efficiency pumping of Rydberg atoms.

[0032] The pump light, reference light, probe light, local oscillator I, local oscillator II, and local oscillator III all originate from the first laser. The first laser emits a continuous, narrow-linewidth laser beam with the same frequency as the transition frequency from the ground state (atomic level 1) to the excited state (atomic level 2) of an alkali metal. The emitted laser beam is sequentially split into several laser beams after passing through beam-splitting prisms 1, 2, 5, I, and II. After the laser beam passes through beam-splitting prism 1, the transmitted light is frequency-shifted again by acousto-optic modulator 1. This laser beam is used as a probe beam. After passing through a plane high-reflection mirror and a piezoelectric ceramic high-reflection mirror, it is transmitted through long-wavelength lens 1 and incident into the alkali metal atom gas cell. After interacting with the alkali metal atoms in the gas cell, it is transmitted through long-wavelength lens 2 and collected by a high-sensitivity signal readout system. The laser beam reflected by beam-splitting prism 1 is incident on beam-splitting prism 2. The laser beam reflected by beam-splitting prism 2 is used as a reference beam. After passing through a plane high-reflection mirror and a piezoelectric ceramic high-reflection mirror, it is transmitted through long-wavelength lens 1. The laser beam, incident on the alkali metal atom gas chamber, interacts with the alkali metal atoms in the chamber and is then transmitted through long-wavelength lens 2 and collected by a high-sensitivity signal readout system. The laser beam transmitted through beam-splitting prism 2 is then incident on beam-splitting prism 5, where the laser beam reflected by beam-splitting prism 5 is frequency-shifted again by acousto-optic modulator 2. This laser beam is used as pump light, and after passing through a plane high-reflection mirror and a piezoelectric ceramic high-reflection mirror, it is transmitted through long-wavelength lens 1 and incident on the alkali metal atom gas chamber. After interacting with the alkali metal atoms in the chamber, it is transmitted through long-wavelength lens 2 and collected by a high-sensitivity signal readout system.

[0033] The laser beam transmitted through beam splitter 5 is incident on beam splitter prism I. Beam splitter prism I splits the incident laser beam into two beams. The reflected light is frequency-shifted by acousto-optic modulator I and used as local oscillator I, which is then coupled into fiber I. The transmitted light is incident on beam splitter prism II and split into two laser beams. The reflected light is used as local oscillator II and coupled into fiber II. The transmitted light is frequency-shifted by acousto-optic modulator II and used as local oscillator III, which is then coupled into fiber III.

[0034] The second laser emits a continuous, narrow-linewidth laser beam with the same frequency as the transition frequency from the alkali metal excited state (atomic level 2) to the Rydberg state (atomic level 3). The emitted laser beam is split into two beams after passing through beam-splitting prism 3. The transmitted laser beam is incident on a plane high-reflection mirror 2, reflected, and then frequency-shifted by an electro-optic modulator, serving as coupling beam 2. After reflection by long-wavelength lens 2, it enters the atomic gas chamber. In the atomic gas chamber, the path of coupling beam 2 coincides with the path of the pump beam in opposite directions. After interacting with atoms, coupling beam 2 is reflected by long-wavelength lens 2 and collected by the optical trash can. The other laser beam, reflected by beam-splitting prism 3, is first emitted through a plane high-reflection mirror 5, then frequency-shifted by an electro-optic modulator, serving as coupling beam 1. After reflection by long-wavelength lens 2, it enters the atomic gas chamber. In the atomic gas chamber, the path of coupling beam 2 coincides with the path of the probe beam in opposite directions. After interacting with atoms, coupling beam 2 is reflected by long-wavelength lens 2 and collected by the optical trash can.

[0035] The phase-locked laser emits a continuous, narrow-linewidth laser beam with the same frequency as the reference beam. After passing through beam-splitting prism 4, the beam is split into two beams. The transmitted beam follows the same path as the reference beam, passing through a plane high-reflection mirror 1 and a piezoelectric ceramic high-reflection mirror, then through a long-wavelength lens 1, an atomic gas cell, and a long-wavelength lens 2. After being reflected by a plane high-reflection mirror 3, the beam enters beam-combining prism 1. The other beam, reflected by beam-splitting prism 4, passes through the plane high-reflection mirror 4 and enters beam-combining prism 1. The two laser beams interfere at beam-combining prism 1, forming an interference signal. The interference signal is obtained using a phase-locked balanced detector, processed, and fed back to the piezoelectric ceramic high-reflection mirror, thus achieving phase-locking of the spatial optical path.

[0036] The frequency of the first laser is locked to the resonance frequency of the transition from the ground state to the excited state of the atom. The probe light is obtained by blue detuning and frequency shifting through acousto-optic modulator 1, and satisfies the large detuning condition, i.e., the detuning frequency is much greater than the Rabi frequency. The pump light is obtained by red detuning and frequency shifting through acousto-optic modulator 2, and also satisfies the large detuning condition, i.e., the detuning frequency is much greater than the Rabi frequency. The frequency of the second laser is locked to the resonance frequency of the transition from the excited state to the Rydberg state of the atom. The laser frequencies of coupling light 1 and coupling light 2 are modulated by electro-optic modulators, respectively. The system is required to satisfy the two-photon resonance excitation conditions of the alkali metal atoms by the probe light and coupling light 1, and the two-photon resonance excitation conditions of the alkali metal atoms by the pump light and coupling light 2.

[0037] This invention relates to a high-sensitivity readout system based on Rydberg atomic microwave measurement data, comprising three optical amplification systems to amplify the pump light, reference light, and probe light signals, respectively. The reference light and probe light have the same frequency, and the three laser beams have relatively low power and are phase-locked looped for phase control. The probe light, reference light, and pump light are controlled with identical optical power and spatial modes, with optical power at the microwatt level. The local oscillator I, local oscillator II, and local oscillator III have optical power at the milliwatt level, satisfying the condition that the optical power of local oscillator I, local oscillator II, and local oscillator III is much greater than the optical power of the pump light, reference light, and probe light.

[0038] Among them, the acousto-optic modulator 1 and acousto-optic modulator II are controlled to make the frequency of the probe light and the local oscillator light III the same. The local oscillator light III is coupled into the single-mode fiber III. The single-mode fiber III is adjusted to make the spatial mode of the local oscillator light III and the probe light the same. The two laser beams are combined and interfered at the beam combining prism III. The local oscillator light III performs a balanced zero-beat amplification process on the probe light. The interference signal is received by the probe light balanced detector and the probe photoelectric signal is output.

[0039] The reference light and the local oscillator II have the same frequency. The local oscillator II is coupled into the single-mode fiber II. The single-mode fiber II is tuned to make the spatial modes of the local oscillator II and the reference light the same. The two laser beams are combined and interfered at the beam combining prism II. The local oscillator II performs a balanced zero-beat amplification process on the reference light. The interference signal is received by the reference light balanced detector and the reference photoelectric signal is output.

[0040] The frequency of the local oscillator I can be altered relative to the pump light frequency by controlling the acousto-optic modulator I. The frequency difference range is (0MHz, +10MHz), which creates a frequency difference between the pump light and the local oscillator I. The local oscillator I is then coupled into the single-mode fiber I. The single-mode fiber I is tuned so that the local oscillator I and the pump light have the same spatial mode. The two laser beams are combined and interfere at the beam combining prism I. The local oscillator I performs a balanced heterodyne amplification process on the probe light. The interference signal is received by the pump light balanced detector and outputs the pump photoelectric signal.

[0041] Using electrical signal receiving devices such as acquisition cards, probe photoelectric signals, reference photoelectric signals, and pump photoelectric signals are received respectively; the reference photoelectric signal is subtracted from the probe photoelectric signal, and noise reduction operation is performed to obtain microwave field intensity information; the reference photoelectric signal is subtracted from the pump photoelectric signal, and noise reduction operation is performed to obtain microwave field phase information.

[0042] In the above description, the pump light, reference light, and probe light interact with the atoms. However, in the optical path of the reference light, there is no modulation by coupling light 1, coupling light 2, and microwave signal; only the atoms absorb the probe light. Therefore, after optical amplification and optical balance zero-beat system reception, the reference light is only used as background noise. On the paths of the pump light and probe light interacting with the atoms, the atoms are simultaneously affected by coupling light 1, coupling light 2, and microwave signal, respectively. This allows the microwave signal to be directly modulated onto the spectra of the probe light and pump light. Therefore, by performing a balanced zero-beat amplification process and a balanced heterodyne process on the probe light and pump light, the readout sensitivity of the microwave intensity information and the readout sensitivity of the microwave phase information of the atomic microwave signal readout system are improved.

[0043] In this invention, the probe light, reference light, pump light, local oscillator I, local oscillator II, and local oscillator III are continuous lasers originating from the same narrow-linewidth laser. The frequencies of the probe light, reference light, and pump light are near the resonance frequency of the transition from the ground state to the excited state of an alkali atom. Coupled light 1 and coupled light 2 are continuous narrow-linewidth lasers with frequencies near the resonance frequency of the transition from the excited state to the Rydberg state of an alkali atom. The probe light and coupled light 1 achieve the two-photon resonance excitation process of the Rydberg atom, and the pump light and coupled light 2 achieve the two-photon resonance excitation process of the Rydberg atom.

[0044] The atomic gas chamber collects probe light, reference light, pump light, coupling light 1, coupling light 2, and microwave signal. Coupling light 1 spatially coincides with the probe light but is in opposite directions. Both laser beams together pump the atoms to the Rydberg state. The frequency of the microwave signal is the Rydberg state energy level (…). Figure 3 The 3rd energy level in the middle) and the adjacent energy level ( Figure 3 The resonant frequency of the 4th energy level in the Rydberg state; the coupling light 2 and the pump light spatially coincide but are in opposite directions, and the two laser beams together pump the atom to the Rydberg state. The frequency of the microwave signal is the resonant frequency of the Rydberg state energy level ( Figure 3 The 3rd energy level in the middle) and the adjacent energy level ( Figure 3 The resonant frequency of the fourth energy level in the atomic gas cell. In the atomic gas cell, the microwave signal interacts with the Rydberg atoms and transmits the information of the microwave signal to the Rydberg atoms. The Rydberg atoms then modulate the probe light and pump light, and finally use the probe light and pump light to read out the information of the microwave signal.

[0045] When the system requires high sensitivity to detect the amplitude information of microwave signals, a balanced zero-beat readout scheme is used, where the local oscillator II and the reference light have the same frequency, and the local oscillator III and the probe light have the same frequency, providing high sensitivity to the amplitude information of microwave signals. When the system needs to detect the phase information of microwave signals, a balanced differential readout scheme is used, where the local oscillator II and the reference light have the same frequency, and the local oscillator I and the pump light have different frequencies, providing high sensitivity to the phase information of microwave signals.

[0046] Alternatively, the atoms manipulated in the atomic gas chamber can be alkali metal atoms, such as rubidium atoms and cesium atoms.

[0047] Example:

[0048] Using rubidium atoms as the manipulated atoms, a high-sensitivity readout system for microwave measurement data based on Rydberg atoms, as described in this invention, will be specifically explained:

[0049] like Figure 3 As shown, the 5S atoms of rubidium are selected. 1 / 2 Energy levels are the ground states of an atom, namely atomic energy level 1 and the 5P energy level of the atom. 3 / 2 As the excited state of the atom, i.e., atomic energy level 2, the 70S energy level of the rubidium atom is selected. 1 / 2 The energy level is the Rydberg state of the atom, namely the atomic energy level 3.

[0050] like Figure 1 , 2 As shown, the probe beam, reference beam, pump beam, local oscillator beam I, local oscillator beam II, and local oscillator beam III are continuous laser beams from the same laser. Several beam splitters are used to split a single beam into multiple parallel laser beams in space, parallel to the tabletop and to each other. The beam waist diameter is approximately 100 μm. The frequency of the laser is locked to the resonance frequency of the transition from the ground state energy level to the excited state energy level of an atom, that is, the resonance frequency from atomic energy level 1 to atomic energy level 2, with a frequency of 384.23034 THz. The optical power intensity of the probe beam, reference beam, and pump beam is controlled at 80 μW. The two laser beams are phase-locked using phase-locking technology.

[0051] Coupled beams 1 and 2 are continuous laser beams from a narrow-linewidth laser, with the laser frequency locked to the resonance frequency of the transition from the excited state to the Rydberg state of the atom, which is 625.05862 THz, i.e., the resonance frequency from atomic level 2 to atomic level 3. The optical power intensity is controlled at 400 mW. At this time, the probe beam, reference beam, and pump beam are injected parallel to each other from the left side of the atomic gas cell, while coupled beams 1 and 2 are injected parallel to each other from the right side of the atomic gas cell. Coupled beam 1 coincides with the probe beam, and coupled beam 2 coincides with the pump beam.

[0052] Observation of Rydberg atom pumping using a high-sensitivity readout system:

[0053] Turn on the microwave signal source and inject a microwave signal with a frequency of 10.68 GHz into the atomic gas cell. This microwave signal resonates with the transition frequency of energy levels 3 and 4 of the Rydberg atom, which can couple the two energy levels together. The information of the microwave signal is modulated onto the probe light and pump light through the Rydberg atom.

[0054] A high-sensitivity readout system is used to read out the information carried by the probe light and pump light. Specifically, when the reference light and local oscillator II, and the probe light and local oscillator III have the same frequency, the optical power of local oscillator II and local oscillator III is controlled to 80mW. The probe light signal is then amplified using balanced zero-beat amplification to achieve high-sensitivity readout of the microwave signal.

[0055] When the reference light and local oscillator II have the same frequency, and the pump light and local oscillator I are detuned by 10MHz, the optical power of local oscillator I and local oscillator II is controlled to be 80mW. The phase information of the microwave signal is read out by using the balanced heterodyne detection optical signal.

[0056] This invention utilizes optical amplification techniques combined with balanced zero-beat detection and balanced heterodyne detection techniques to rapidly improve the sensitivity and phase information acquisition of atomic microwave measurement systems, greatly reducing the difficulty of controlling atomic systems and increasing the applicability of atomic microwave measurement systems.

[0057] This invention utilizes local oscillator I, local oscillator II, and local oscillator III to perform optical amplification on pump light, reference light, and probe light signals, respectively, to achieve a system with high-sensitivity readout of microwave signal intensity information and direct readout of phase information. By manipulating local oscillator I, local oscillator II, and local oscillator III to achieve data readout technology, the sensitivity of data reading in the atomic microwave measurement system is improved.

[0058] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A microwave measurement high-sensitivity readout system for a Rydberg atomic pump system, characterized in that: Includes beam splitter prism I, beam splitter prism II, beam combiner prism I, beam combiner prism II, beam combiner prism III, acousto-optic modulator I, acousto-optic modulator II, single-mode fiber I, single-mode fiber II, single-mode fiber III, plane high-reflection mirror I, plane high-reflection mirror II, plane high-reflection mirror III, plane high-reflection mirror IV, pump light balanced detector, reference light balanced detector, and probe light balanced detector; The local oscillating light is split into two paths after passing through beam splitter I. One path, as the local oscillating light I, is reflected to acousto-optic modulator I for acousto-optic modulation. The modulated optical signal is coupled into single-mode fiber I and incident on plane high-reflection mirror II. The other path, as the transmitted light I, is transmitted to beam splitter II and processed into two optical paths. One path, as the local oscillating light II, is coupled into single-mode fiber II and incident on plane high-reflection mirror III. The other path, as the transmitted light II, is transmitted to plane high-reflection mirror I and reflected by plane high-reflection mirror I to obtain local oscillating light III. Local oscillating light III is coupled into single-mode fiber III and incident on plane high-reflection mirror IV. The single-mode fiber I is tuned so that the local oscillator I and the pump light have the same spatial mode. The local oscillator I reflected by the plane high-reflection mirror II and the pump light emitted from the Rydberg atomic pump system are combined and interfered at the beam combining prism I. The local oscillator I performs balanced heterodyne amplification on the pump light. The interference signal is received by the pump light balanced detector and the pump photoelectric signal is output. The single-mode fiber II is tuned to make the spatial modes of the local oscillator II and the reference light the same. The local oscillator II reflected by the plane high-reflection mirror III and the reference light emitted from the Rydberg atomic pump system are combined and interfered at the beam combining prism II. The local oscillator II performs balanced zero-beat amplification on the probe light. The interference signal is received by the reference light balanced detector and the reference photoelectric signal is output. The single-mode fiber III is tuned so that the local oscillator III and the probe light have the same spatial mode. The local oscillator III emitted by the plane high-reflection mirror IV and the probe light emitted by the Rydberg atomic pump system are combined and interfered at the beam combining prism III. The local oscillator III performs balanced zero-beat amplification on the probe light. The interference signal is received by the probe light balanced detector and outputs the probe photoelectric signal.

2. The microwave measurement high-sensitivity readout system for a Rydberg atomic pump system according to claim 1, characterized in that: Using an electrical signal receiving device, a detection photoelectric signal, a reference photoelectric signal, and a pump photoelectric signal are received respectively. The reference photoelectric signal is subtracted from the detection photoelectric signal, and the noise reduction operation is performed to obtain microwave intensity information. The reference photoelectric signal is subtracted from the pump photoelectric signal, and the noise reduction operation is performed to obtain microwave phase information.

3. The microwave measurement high-sensitivity readout system for a Rydberg atomic pump system according to claim 1, characterized in that: The Rydberg atomic pumping system comprises a first laser, a second laser, a glass gas chamber containing alkali metal atoms, a heating plate, a first beam splitter prism, a first acousto-optic modulator, a second acousto-optic modulator, a second beam splitter prism, a first plane high-reflection mirror, a second plane high-reflection mirror, a third plane high-reflection mirror, a fourth plane high-reflection mirror, a fifth plane high-reflection mirror, a piezoelectric ceramic high-reflection mirror, a first long-wavelength lens, a second long-wavelength lens, a phase-locked balanced detector, a third beam splitter prism, a first electro-optic modulator, a second electro-optic modulator, an optical trash can, a phase-locked laser, a fourth beam splitter prism, a fifth beam splitter prism, and a first beam combiner prism. A glass gas chamber containing alkali metal atoms is located between two heating plates. The heating plates are energized to heat the atomic gas chamber. A first laser emits a continuous laser beam, which is split into two beams by a first beam-splitting prism. One beam is transmitted through the first beam-splitting prism and then frequency-shifted by a first acousto-optic modulator to be used as a probe beam. The other beam is split into two beams again by a second beam-splitting prism. One beam is reflected by the second beam-splitting prism and used directly as a reference beam. The other beam is split into two beams again by a fifth beam-splitting prism. One beam is reflected by the fifth beam-splitting prism and then frequency-shifted by a second acousto-optic modulator to be used as a pump beam. The other beam is incident on beam-splitting prism I as a local oscillation beam. The probe beam, pump beam, and reference beam are three parallel laser beams. They are reflected by the first planar high-reflection mirror and the piezoelectric ceramic high-reflection mirror into three beams parallel to the heating plate. After being transmitted through the first long-wavelength lens, they enter the glass gas chamber from one side. The phase-locked laser emits a continuous phase-locked laser, which is split into two beams by a fourth beam-splitting prism. One of the phase-locked laser beams travels the same path as the probe beam in space. After being reflected by a first plane high-reflection mirror and a piezoelectric ceramic high-reflection mirror, it is parallel to the heating plate and enters the glass gas chamber from one side. It passes through the glass gas chamber and is incident on a third plane high-reflection mirror. After being reflected by the third plane high-reflection mirror, it is combined with another phase-locked laser beam that has passed through a fourth plane high-reflection mirror and a first beam-combining prism in sequence to beat the frequency. The beat frequency signal is received by a phase-locked balanced detector. The second laser emits a continuous laser beam, which is split into two beams by a third beam-splitting prism. One beam is transmitted through the third beam-splitting prism and reflected by a second high-reflection mirror. After being modulated by a second electro-optic modulator, it is used as the second coupling beam. The other beam is reflected by the third beam-splitting prism and incident on a fifth high-reflection mirror. After being reflected by the fifth high-reflection mirror, it is modulated by the second electro-optic modulator and used as the second coupling beam. The first and second coupling beams are reflected by a second long-wavelength lens and enter the glass gas cell from the other side. The first coupling beam coincides with the probe beam, and the second coupling beam coincides with the pump beam. After interacting with atoms, the first and second coupling beams are reflected by a first long-wavelength lens and received by an optical garbage bin. The probe light, pump light, and reference light are emitted from a glass gas cell containing alkali metal atoms.

4. The microwave measurement high-sensitivity readout system for a Rydberg atomic pump system according to claim 1, characterized in that: The optical power of local oscillator I, local oscillator II, and local oscillator III is much greater than that of the pump light, reference light, and probe light.

5. The microwave measurement high-sensitivity readout system for a Rydberg atomic pump system according to claim 1, characterized in that: The probe light and the local oscillator III have the same frequency.

6. The microwave measurement high-sensitivity readout system for a Rydberg atomic pump system according to claim 1, characterized in that: The reference beam and the local oscillator beam II have the same frequency.

7. The microwave measurement high-sensitivity readout system for a Rydberg atomic pump system according to claim 1, characterized in that: Controlling the acousto-optic modulator I changes the frequency of the local oscillator I to be detuned relative to the pump light frequency, so that there is a frequency difference between the pump light and the local oscillator I.

8. The microwave measurement high-sensitivity readout system for a Rydberg atomic pump system according to claim 3, characterized in that: The frequency of the first laser is locked to the resonance frequency of the transition from the ground state to the excited state of an atom.

9. The microwave measurement high-sensitivity readout system for a Rydberg atomic pump system according to claim 3, characterized in that: The frequency of the second laser is locked to the resonance frequency of the transition from the excited state level to the Rydberg state level of the atom.

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