Alkali metal atom gas chamber based on Rydberg electric field measurement and electric field measurement device

Abstract

The invention discloses an alkali metal atom gas chamber based on Rydberg electric field measurement and an electric field measurement device. The problem of electric field shielding during electric field measurement is solved. According to the invention, the square glass with high purity and low conductivity is selected as the air chamber main body, so that the air chamber main body has good optical transparency and chemical stability. By selecting metal with high conductivity and low resistivity, effective transmission of inductive charge signals is ensured. Glass and metal are subjected to laser welding, so that no air leakage is ensured. The atom gas chamber is firstly vacuumized, then alkali metal atoms are injected, and stable atom steam is formed. The Rydberg atomic glass gas chamber is simple in structure, interference of an external stray electric field is reduced, measurement stability is improved, the shielding effect of a traditional Rydberg atomic glass gas chamber in low-frequency electric field measurement is effectively overcome through a unique metal-glass composite structure, and sensitivity and accuracy of electric field measurement are improved.

Description

Technical Field

[0001] The present application relates to the field of electric field measurement, and particularly to an alkali metal atomic gas cell and an electric field measurement device based on Rydberg electric field measurement. Background Art

[0002] Electric field sensors play an important role in fields such as electric power and national defense. With the rapid development of electric power technology, high-voltage direct current (HVDC) transmission systems have become an important part of the modern power grid structure. Quantum measurements based on Rydberg atoms rely on the Stark effect of electric fields on Rydberg atoms, using quantum coherent spectroscopy to measure energy level splitting and inferring electric field strength information. It has excellent characteristics such as high measurement accuracy, traceability to fundamental physical constants, and anti-electric field interference.

[0003] However, when a Rydberg atom electric field sensor measures low-frequency electric fields below kHz, a common technical problem is the electric field shielding effect. The specific mechanism is that after Rydberg atoms adsorb to the inner glass surface, free electrons are generated under the action of factors such as laser excitation, thermal motion collisions, or external electric field induction, thus forming a spatially closed conductive layer. Similar to the shielding effect of metals on external electric fields, free electrons are rearranged on the surface of the conductive layer, thereby shielding the external low-frequency or direct current electric field and causing the measurement method to fail.

[0004] Therefore, how to solve the electric field shielding problem during electric field measurement is a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0005] The purpose of the present application is to provide an alkali metal atomic gas cell and an electric field measurement device based on Rydberg electric field measurement to solve the electric field shielding problem during electric field measurement.

[0006] To solve the above technical problem, the present application provides an alkali metal atomic gas cell based on Rydberg electric field measurement. The alkali metal atomic gas cell has a cubic structure and includes: two pairs of oppositely arranged glass surfaces, including: a first pair of opposite glass surfaces and a second pair of opposite glass surfaces; a pair of oppositely arranged metal surfaces;

[0007] The metal surfaces are welded to the glass surfaces by pulsed laser; the metal surfaces are perpendicular to the direction of the electric field to be measured;

[0008] Among them, the first pair of opposite glass surfaces are used for passing the probe light and the pump light that are oppositely emitted; in the second pair of opposite glass surfaces, a through hole is provided in the middle of one of the glass surfaces, and the through hole is used for evacuating the alkali metal atomic gas cell and sealing alkali metal atoms.

[0009] As an alternative solution, in the above alkali metal atomic gas cell based on Rydberg electric field measurement,

[0010] The through-hole welded glass tube, the glass tube is used to evacuate the alkali metal atomic gas chamber by connecting to a vacuum device;

[0011] The alkali metal gas filling device injects alkali metal atoms through the glass tube.

[0012] As an alternative, in the above alkali metal atomic gas chamber based on Rydberg electric field measurement, through holes perpendicular to the opposite end faces are respectively opened on the first opposite glass surfaces, and glass sheets serving as optical windows are respectively anodic bonded to the glass surfaces provided with the through holes.

[0013] As an alternative, in the above alkali metal atomic gas chamber based on Rydberg electric field measurement, it further includes: a ground wire; the metal surface is connected to the ground wire.

[0014] As an alternative, in the above alkali metal atomic gas chamber based on Rydberg electric field measurement, the relative distance between the opposite metal surfaces and the opposite glass surfaces does not exceed 15 mm.

[0015] As an alternative, in the above alkali metal atomic gas chamber based on Rydberg electric field measurement, the material of the glass surface is borosilicate glass or quartz glass.

[0016] As an alternative, in the above alkali metal atomic gas chamber based on Rydberg electric field measurement, the Ra value of the roughness of the glass surface is not greater than 0.05 μm.

[0017] As an alternative, in the above alkali metal atomic gas chamber based on Rydberg electric field measurement, the vacuum pressure of the alkali metal atomic gas chamber is not higher than 10 -3 Pa.

[0018] As an alternative, in the above alkali metal atomic gas chamber based on Rydberg electric field measurement, the alkali metal atoms are cesium or rubidium.

[0019] To solve the above technical problems, the present application further provides an electric field measurement device, including the above alkali metal atomic gas chamber based on Rydberg electric field measurement.

[0020] The alkali metal atomic cell provided by this application, based on Rydberg electric field measurement, has a cubic structure and includes: two pairs of oppositely arranged glass surfaces and a pair of oppositely arranged metal surfaces; the metal surfaces and the glass surfaces are welded by high-energy pulsed laser; the direction of the metal surfaces is parallel to the direction of the electric field to be measured; among them, the surface of the first pair of opposite glass surfaces is smooth and is used for the counter-propagating probe light and pump light; in the second pair of opposite glass surfaces, there is a through hole in the middle of one of the glass surfaces, and the through hole is used for evacuating the alkali metal atomic cell and sealing the alkali metal atoms. This application selects square glass with high purity and low conductivity as the main body of the cell to ensure good optical transparency and chemical stability. By selecting metals with high conductivity and low resistivity, the effective transmission of the induced charge signal is ensured. By laser welding the glass and the metal, air leakage is ensured to be avoided. The atomic cell is first evacuated and then filled with alkali metal atoms to form a stable atomic vapor. The interference of external stray electric fields is reduced, and the measurement stability is improved. Through the unique metal-glass composite structure, the shielding effect in the low-frequency electric field measurement of traditional Rydberg atomic glass cells is effectively overcome, and the sensitivity and accuracy of electric field measurement are improved.

[0021] In addition, this application also provides an electric field measurement device, including the above-mentioned alkali metal atomic cell based on Rydberg electric field measurement, and the effect is the same as above. Description of the Drawings

[0022] In order to more clearly illustrate the embodiments of this application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of this application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 Schematic diagram of an alkali metal atomic cell provided for an embodiment of this application;

[0024] Figure 2 Schematic diagram of an electric field measurement device provided for an embodiment of this application;

[0025] Figure 3 Schematic diagram of frequency shift measurement and frequency calibration provided for an embodiment of this application.

[0026] Reference Signs:

[0027] 10 - Metal surface; 20 - First opposing glass surface; 30 - Second opposing glass surface; 11 - Probe light laser; 12 - Pump light laser; 21 - Probe light isolator; 22 - Pump light isolator; 31 - First wave plate; 32 - Second wave plate; 41 - First beam splitter; 42 - Second beam splitter; 51 - First mirror; 52 - Second mirror; 61 - First dichroic mirror; 62 - Second dichroic mirror; 63 - Third dichroic mirror; 64 - Fourth dichroic mirror; 71 - Reference atomic gas cell; 72 - Measurement atomic gas cell; 81 - Reference photodetector; 82 - Measurement photodetector; 91 - Reference electro-optic modulator; 92 - Measurement electro-optic regulator; 13 - RF source; 14 - Data processing device. Detailed implementation mode

[0028] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the protection scope of the present application.

[0029] The core of the present application is to provide an alkali metal atomic gas cell and an electric field measurement device based on Rydberg electric field measurement.

[0030] In order to enable those skilled in the art to better understand the solution of the present application, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation modes.

[0031] To solve the above problems, this embodiment provides an alkali metal atomic gas cell based on Rydberg electric field measurement. The alkali metal atomic gas cell has a cubic structure and includes: two pairs of opposing glass surfaces, including: the first opposing glass surface 20 and the second opposing glass surface 30; a pair of opposing metal surfaces 10;

[0032] The metal surface 10 is pulse laser welded to the glass surface; the metal surface is perpendicular to the direction of the electric field to be measured;

[0033] Among them, the first opposing glass surface 20 is used to pass the probe light and the pump light that are emitted towards each other; in the second opposing glass surface 30, a through hole is provided in the middle of one of the glass surfaces, and the through hole is used to evacuate the alkali metal atomic gas cell and seal the alkali metal atoms.

[0034] This embodiment proposes an alkali metal atomic gas cell based on Rydberg electric field measurement. The gas cell has a cubic structure and is mainly composed of two pairs of opposing glass surfaces and a pair of opposing metal surfaces 10.

[0035] Two pairs of oppositely arranged glass surfaces include: The first pair of opposite glass surfaces 20: with a smooth surface, used for the detection light and pump light that are emitted towards each other. This design ensures that the detection light and pump light can pass through the glass surface unobstructed and interact with the alkali metal atoms in the gas chamber.

[0036] The second pair of opposite glass surfaces 30: There is a through-hole in the middle of one of the glass surfaces, and this through-hole is used for evacuating the alkali metal atom gas chamber and sealing the alkali metal atoms. The design of the through-hole facilitates the vacuum treatment of the gas chamber and the filling and sealing of alkali metal atoms.

[0037] The glass material is preferably a square glass with high purity and low conductivity, ensuring its good optical transparency and chemical stability.

[0038] A pair of oppositely arranged metal surfaces 10, and the direction of the metal surfaces 10 is parallel to the direction perpendicular to the electric field to be measured. This design enables the metal surfaces 10 to effectively sense and conduct the electric field to be measured, improving the sensitivity of electric field measurement. The metal material should be a metal with high conductivity and low resistivity, such as copper, aluminum, etc., to ensure the effective transmission of the induced charge signal.

[0039] The metal surfaces 10 and the glass surfaces are connected by high-energy pulsed laser welding. Achieved through high-energy pulsed laser welding, it ensures the airtightness of the gas chamber and the firm connection between the metal surfaces 10 and the glass surfaces. This connection effectively avoids the leakage of alkali metal atoms in the gas chamber and at the same time improves the sensitivity of electric field measurement. Under certain specific conditions, other connection methods (such as bonding, mechanical fixing, etc.) can be considered to replace high-energy pulsed laser welding, but attention should be paid to maintaining the airtightness of the gas chamber and the firmness of the connection.

[0040] The alkali metal atoms can be filled with alkali metal atoms such as cesium (Cs) or rubidium (Rb), and these atoms have a long lifetime and a high polarizability, which are suitable for Rydberg electric field measurement.

[0041] The alkali metal atom gas chamber of this embodiment is particularly suitable for low-frequency electric field measurement, especially for ultra-low-frequency electric fields and DC electric field measurements including power frequency electric field frequencies. Its unique metal-glass composite structure effectively overcomes the shielding effect of traditional Rydberg atom glass gas chambers in low-frequency electric field measurement and can be applied to precise electric field measurement in fields such as scientific research, industrial detection, and environmental monitoring.

[0042] Before measurement, the gas chamber needs to be in a vacuum state to avoid interference from air molecules to the measurement. During measurement, the gas chamber is filled with stable alkali metal atom vapor. The intensity of the external electric field is deduced by detecting the change in the spectral characteristics of Rydberg atom electromagnetically induced transparency (EIT). The specific operations include locking the detection light frequency, scanning the pump light frequency, observing the EIT spectral shift, etc.

[0043] In some application scenarios, it may be necessary to add an additional electromagnetic shielding layer or a temperature control device outside the gas chamber to reduce external electromagnetic interference or maintain the temperature stability inside the gas chamber.

[0044] Through the alkali metal atom gas chamber based on Rydberg electric field measurement provided by this embodiment, the alkali metal atom gas chamber has a cubic structure, including: two pairs of oppositely arranged glass surfaces, and a pair of oppositely arranged metal surfaces 10; the metal surfaces 10 are welded to the glass surfaces by high-energy pulsed laser; the direction of the metal surfaces 10 is parallel to the direction of the electric field to be measured; wherein, the surface of the first pair of opposite glass surfaces 20 is smooth, for passing the probing light and the pumping light that are emitted towards each other; in the second pair of opposite glass surfaces 30, there is a through hole in the middle of one of the glass surfaces, and the through hole is used for evacuating the alkali metal atom gas chamber and sealing the alkali metal atoms. In this application, by selecting square glass with high purity and low conductivity as the main body of the gas chamber, it is ensured that it has good optical transparency and chemical stability. By selecting metal with high conductivity and low resistivity, it is ensured that the induced charge signal can be effectively transmitted. By laser welding the glass and the metal, air leakage is ensured to be avoided. First, the air in the atom gas chamber is evacuated, and then alkali metal atoms are injected to form a stable atomic vapor. The interference of external stray electric fields is reduced, and the measurement stability is improved. Through the unique metal-glass composite structure, the shielding effect of traditional Rydberg atom glass gas chambers in low-frequency electric field measurement is effectively overcome, and the sensitivity and accuracy of electric field measurement are improved.

[0045] According to the above embodiment, in a specific embodiment, a glass tube is welded to the through hole, and the glass tube is connected to an evacuation device to evacuate the alkali metal atom gas chamber;

[0046] The alkali metal gas filling device injects alkali metal atoms through the glass tube.

[0047] In the above design of the alkali metal atom gas chamber based on Rydberg electric field measurement, as an optional improvement scheme, a glass tube can be welded to the side of the second pair of opposite glass surfaces 30 with a through hole by high-energy pulsed laser welding technology. This glass tube plays two key roles in the design:

[0048] Evacuation channel: The glass tube is connected to an external evacuation device to form a closed evacuation system. By starting the evacuation device, the air and other impurities inside the alkali metal atom gas chamber can be effectively pumped out to reach the required vacuum degree.

[0049] Alkali metal atom injection channel: After the evacuation operation is completed, the glass tube can also be used as the access point for the alkali metal gas filling device. Through this glass tube, accurately metered alkali metal atoms (such as cesium, rubidium, etc.) can be injected into the gas chamber in the form of gas to form a stable alkali metal atomic vapor.

[0050] In a specific embodiment, the alkali metal atom is cesium or rubidium. Both cesium and rubidium belong to alkali metal elements and have similar chemical properties, such as strong reactivity and easy loss of electrons.

[0051] Connect the vacuum pumping device to the glass tube and start the vacuum pumping procedure. During the vacuum pumping process, closely monitor the pressure change in the gas chamber to ensure that the required vacuum degree standard is achieved. After completing the vacuum pumping, disconnect the vacuum pumping device from the glass tube and connect the alkali metal gas filling device to the glass tube. Slowly inject the alkali metal atoms in the form of gas into the gas chamber by precisely controlling the output and injection speed of the filling device. After the injection is completed, wait for a period of time to allow the alkali metal atoms to be evenly distributed in the gas chamber and form a stable vapor.

[0052] By welding the glass tube as the channel for vacuum pumping and alkali metal atom injection, complex operations directly on the gas chamber wall are avoided, improving the convenience and operability of the entire preparation process. The high-energy pulsed laser welding technology ensures a firm connection between the glass tube and the gas chamber wall, effectively preventing the leakage of alkali metal atoms and the intrusion of external impurities, enhancing the sealing and stability of the gas chamber. The stable alkali metal atom vapor and high-efficiency electric field induction ability enable the gas chamber to exhibit higher sensitivity and accuracy in low-frequency electric field measurement, providing strong support for precise electric field measurement in fields such as scientific research, industrial detection, and environmental monitoring.

[0053] According to the above embodiment, in a specific embodiment, through holes perpendicular to the opposite end faces are respectively formed on the first opposite glass surfaces 20, and glass sheets serving as optical windows are respectively anodic bonded to the glass surfaces provided with the through holes.

[0054] In a specific embodiment of the present invention, the first opposite glass surfaces 20 (i.e., one or both of a pair of glass surfaces opposite to the metal surface 10) are designed to be provided with through holes perpendicular to the opposite end faces. The purpose of these through holes is to allow the probe light and the pump light to pass through, so as to interact with the alkali metal atoms in the gas chamber.

[0055] On the glass surfaces provided with the through holes, glass sheets serving as optical windows are respectively connected by anodic bonding technology. Anodic bonding is a process method that utilizes the chemical reaction between glass and metal at high temperature to form a firm connection. This bonding method has high strength, high airtightness, and good optical transparency, and is very suitable for the atomic gas chamber structure of the present invention.

[0056] The anodic-bonded glass sheet serves as an optical window with high light transmittance, ensuring that the detection light and pump light can pass through with minimal loss, thereby effectively interacting with the alkali metal atoms in the gas chamber. The optical window not only plays a role in transmitting light but also protects the interior of the gas chamber from external contamination and interference. The firm connection formed by anodic bonding can effectively prevent the leakage of alkali metal atoms in the gas chamber and the intrusion of external impurities. The anodic bonding technology not only provides good sealing performance but also enhances the stability of the entire gas chamber structure, making it exhibit higher reliability and durability in low-frequency electric field measurements.

[0057] The position, size, and number of the through holes need to be precisely designed according to the beam diameters, divergence angles of the detection light and pump light, and the overall size of the gas chamber to ensure that the light can pass through efficiently and interact with the alkali metal atoms. No specific settings are made in this embodiment.

[0058] The glass sheet serving as the optical window needs to have characteristics such as high light transmittance, low absorption, and low scattering. At the same time, its thermal expansion coefficient should match that of the main body glass of the gas chamber to avoid excessive internal stress during the high-temperature bonding process.

[0059] Through the above design, the atomic gas chamber of the present invention not only has high-efficiency optical light transmission performance but also has good sealing performance and structural stability, providing strong support for the high-precision measurement of low-frequency electric fields.

[0060] According to the above embodiment, in a specific embodiment, it further includes: a ground wire; the metal surface 10 is connected to the ground wire.

[0061] In another specific embodiment of the present invention, in addition to the previously described structure, it further includes a ground wire. The ground wire is used to connect to the metal surface 10 to ensure the stability and accuracy of the device when measuring low-frequency electric fields.

[0062] By connecting the metal surface 10 to the ground wire, the charge induced on the metal surface 10 can be effectively introduced into the ground, thereby reducing the influence of the electromagnetic shielding effect on the measurement result. This helps to improve the sensitivity and accuracy of the device in low-frequency electric field measurements. The grounding treatment can reduce the interference of external stray electric fields on the device, making the measurement result more stable and reliable. This is particularly important for application scenarios that require long-term continuous measurement.

[0063] The ground wire should be made of a material with good electrical conductivity, corrosion resistance, and wear resistance to ensure its reliability and stability during long-term use. A reliable connection method, such as welding or crimping, should be used between the metal surface 10 and the ground wire to ensure good electrical contact and mechanical strength. The grounding resistance of the ground wire should be as small as possible to reduce the voltage drop and energy loss during grounding. This can be achieved by selecting appropriate grounding materials and optimizing the layout of the ground wire.

[0064] Through the above design, the device of the present invention not only has high-efficiency low-frequency electric field measurement performance, but also has good electromagnetic shielding effect and measurement stability. The addition of the ground wire further improves the practicability and reliability of the device.

[0065] According to the above embodiment, in a specific embodiment, the relative distance between the opposite metal surfaces and the opposite glass surfaces does not exceed 15 mm.

[0066] In a specific embodiment, the relative distance between the opposite metal surface 10 and the opposite glass surface does not exceed 15 mm. This design ensures a tight fit between the metal surface 10 and the glass surface, which is beneficial to achieving good electromagnetic shielding effect and optical performance. By controlling the relative distance between the two, the overall performance of the device can be further optimized to meet specific application requirements. For example, in scenarios where precise measurement of low-frequency electric fields is required, this tight fit can reduce external interference and improve the accuracy and stability of the measurement.

[0067] According to the above embodiment, in a specific embodiment, the material of the glass surface is borosilicate glass or quartz glass.

[0068] In a specific embodiment, the material of the glass surface can indeed be borosilicate glass or quartz glass.

[0069] Borosilicate glass is known for its high light transmittance, good chemical stability and thermal stability, and is very suitable for applications that need to withstand certain temperature and chemical corrosion environments. In applications such as alkali metal lasers or atomic gas cells, borosilicate glass can effectively prevent physical or chemical reactions between alkali metal elements and the cavity wall, thereby prolonging the life of alkali metal elements and improving the stability and reliability of the equipment.

[0070] Quartz glass has higher light transmittance and lower thermal expansion coefficient, and can maintain stable performance under extreme temperature conditions. The excellent optical performance and chemical inertness of quartz glass make it an ideal material for high-performance optical devices and sensor devices. In applications that require high-precision optical measurement and long-term stability requirements, quartz glass can be selected as the glass surface.

[0071] Therefore, according to specific application requirements and working environments, borosilicate glass or quartz glass can be selected as the material of the glass surface to meet the performance requirements of the equipment.

[0072] According to the above embodiment, in a specific embodiment, the Ra value of the roughness of the glass surface is not greater than 0.05 μm.

[0073] In a specific embodiment, the Ra value of the glass surface is not greater than 0.05 μm. This requirement ensures that the glass surface has extremely high smoothness and flatness, which is particularly important for applications that require high-precision optical performance or electromagnetic shielding effects.

[0074] Surface roughness (Ra) is an important indicator for measuring the microscopic geometric shape error of the glass surface, which reflects the average height difference of the tiny peaks and valleys on the glass surface. When the Ra value is small, it indicates that the glass surface is smoother, which helps to reduce light scattering and electromagnetic wave reflection, thereby improving the light transmittance of optical devices and the performance of electromagnetic shielding devices. In practical applications, precise polishing processes can be used to precisely control the surface roughness of the glass.

[0075] According to the above embodiment, in a specific embodiment, the vacuum pressure of the alkali metal atomic cell is not higher than 10 - 3 Pa.

[0076] The vacuum pressure of the alkali metal atomic cell is not higher than 10 -3 Pa, this requirement ensures that the interior of the alkali metal atomic cell has an extremely low pressure environment, which is crucial for the stable existence and performance of alkali metal atoms.

[0077] The control of the internal vacuum degree of the alkali metal atomic cell directly affects the lifetime, density of alkali metal atoms, and their interaction with other particles, thereby affecting the performance and accuracy of the entire device. Therefore, when preparing the alkali metal atomic cell, high-precision vacuum filling equipment and quality control technologies are required to ensure that the internal vacuum degree of the cell meets the design requirements.

[0078] Specifically, a vacuum pressure not higher than 10 -3 Pa can effectively reduce the number of gas molecules inside the cell, thereby reducing the collision frequency between alkali metal atoms and gas molecules, and reducing energy loss and scattering effects. This helps to improve the stability and coherence time of alkali metal atoms, and further enhances the sensitivity and accuracy of quantum sensing instruments.

[0079] In addition, the low vacuum pressure can also reduce impurities and contaminants inside the cell, protecting alkali metal atoms from chemical corrosion and physical damage, and further extending their service life and maintaining high performance.

[0080] Finally, the present application provides an electric field measurement device, including the above-mentioned alkali metal atomic cell based on Rydberg electric field measurement.

[0081] Figure 2A schematic diagram of an electric field measurement device provided in an embodiment of the present application, including a detection light laser 11, a pump light laser 12, a detection light isolator 21, a pump light isolator 22, a first wave plate 31, a second wave plate 32, a first beam splitter 41, a second beam splitter 42, a first reflector 51, a second reflector 52, a first dichroic mirror 61, a second dichroic mirror 62, a third dichroic mirror 63, a fourth dichroic mirror 64, a reference atomic gas chamber 71, a measurement atomic gas chamber 72, a reference photodetector 81, a measurement photodetector 82, a reference electro-optic modulator 91, a measurement electro-optical adjuster 92, a radio frequency source 13, and a data processing device 14. The measurement atomic gas chamber 72 in the figure is the alkali metal atomic gas chamber based on Rydberg electric field measurement.

[0082] Will be like Figure 2 The probe light frequency is locked to the ground state 6S of Cs atoms. 1 / 2 , F=4 and excited state 6P 3 / 2 , F=5 transition, for the pump light laser frequency in the excited state 6P 3 / 2 , F=5 and Rydberg state transitions are scanned, and EIT spectrum appears at the transition. The electric field to be measured is applied to the alkali metal atom gas cell, and the electric field to be measured is coupled with the Rydberg atom. Due to the Stark effect, the Rydberg atom energy level undergoes frequency shift, and then the frequency shift Δν is observed in the EIT spectrum. Figure 3 This is a schematic diagram of frequency shift measurement and frequency calibration provided in an embodiment of the present application. Figure 3 As shown. The formula for calculating the field strength of the electric field to be measured is Δν=α·|E| 2 / 2 .

[0083] Where Δν represents the EIT spectrum frequency shift, which is obtained by comparing the main peak in the spectrum of the reference atomic gas cell 71 with the RF modulation sideband f RF As a frequency standard, the spectral frequency shift measurement is performed. α represents the polarizability of the selected Rydberg atom, which can be calculated using the AtomCalculator program. E represents the electric field strength in the measured atomic gas chamber 72.

[0084] After the electric field measurement device is assembled, strict electric field strength calibration is required. A low-frequency electric field of known intensity is applied for testing to obtain the attenuation factor of the device to the actual electric field and ensure the accuracy of the measurement results in the actual working scenario.

[0085] The above has introduced in detail the alkali metal atomic gas cell and the electric field measurement device based on Rydberg electric field measurement provided by this application. The various embodiments in the specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple. For the relevant parts, reference can be made to the description in the method part. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of this application, several improvements and modifications can be made to this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

[0086] It should also be noted that in this specification, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including the said element.

Claims

1. An alkali metal atom gas cell based on Rydberg electric field measurement, characterized in that: The alkali metal atom gas chamber is a cubic structure, comprising: two pairs of oppositely disposed glass surfaces, including: a first oppositely disposed glass surface and a second oppositely disposed glass surface; and a pair of oppositely disposed metal surfaces; The metal surface and the glass surface are welded by pulse laser; the metal surface is perpendicular to the direction of the electric field to be measured; The first opposing glass surfaces are used to pass the detection light and pump light that are incident on each other; in the second opposing glass surfaces, a through hole is provided in the middle of one of the glass surfaces, and the through hole is used to evacuate the alkali metal atom gas chamber and seal the alkali metal atoms.

2. The alkali metal atom gas cell based on Rydberg electric field measurement according to claim 1, characterized in that: The through hole is welded with a glass tube, and the glass tube is connected to a vacuum pumping device to evacuate the alkali metal atom gas chamber; The alkali metal gas filling device injects alkali metal atoms through the glass tube.

3. The alkali metal atom gas cell based on Rydberg electric field measurement according to claim 1, characterized in that: The first relative glass surfaces are respectively provided with through holes perpendicular to the relative end surfaces, and glass sheets serving as optical windows are respectively connected to the glass surfaces with the through holes by anodizing bonding.

4. The alkali metal atom gas cell based on Rydberg electric field measurement according to claim 1, characterized in that: Also includes: Grounding wire; the metal surface is connected to the grounding wire.

5. The alkali metal atom gas cell based on Rydberg electric field measurement according to claim 4, characterized in that: The relative distance between opposite metal surfaces and opposite glass surfaces shall not exceed 15 mm.

6. The alkali metal atom gas cell based on Rydberg electric field measurement according to claim 1, characterized in that: The glass surface is made of borosilicate glass or quartz glass.

7. The alkali metal atom gas cell based on Rydberg electric field measurement according to claim 1, characterized in that: The roughness Ra value of the glass surface is no greater than 0.05 μm.

8. The alkali metal atom gas cell based on Rydberg electric field measurement according to claim 2, characterized in that: The vacuum pressure of the alkali metal atom gas chamber is not higher than 10 -3 Pa.

9. The alkali metal atom gas cell based on Rydberg electric field measurement according to claim 1, characterized in that: The alkali metal atom is cesium or rubidium.

10. An electric field measuring device, characterized in that: An alkali metal atom gas cell based on Rydberg electric field measurement comprising any one of claims 1 to 9.

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