Atomic clock with adjustable working temperature and preparation method

Abstract

The invention relates to the technical field of precise spectrum detection, and discloses a working temperature adjustable atomic clock and a preparation method, the atomic clock comprises a packaging shell, and a laser source, a light intensity adjusting part, an atomic gas chamber, a temperature control part, a detection part and a frequency locking module which are arranged in the packaging shell, the light intensity adjusting component is arranged between the laser source and the atomic gas chamber, the light intensity adjusting component is used for adjusting the light intensity of laser before the laser enters the atomic gas chamber, the atomic gas chamber comprises a transparent glass bulb, alkali metal and background gas, the transparent glass bulb is filled with the alkali metal and the background gas, and the temperature control component is arranged outside the atomic gas chamber. The heating component is used for heating and maintaining the atomic gas chamber to a preset temperature, the preset temperature is adjustable, the detection component is used for detecting the light intensity of the laser after penetrating through the atomic gas chamber, and the frequency locking module is used for controlling the laser frequency emitted by the laser source according to a detection signal of the detection component. The atomic clock is wide in application range and good in practicability and use flexibility.

Description

Technical Field

[0001] The present invention relates to the technical field of precision spectrum detection, and in particular to an atomic clock with adjustable working temperature and a preparation method thereof. Background Art

[0002] Atomic gas chambers that contain hot atoms are widely used in the field of quantum precision measurement. Atomic gas chambers are usually made of glass fusion to create a sealed and light-transmitting chamber. At the same time, high-purity inert gas or alkali metal atoms are mixed and sealed with a specific ratio of gas to form the core sensitive component of the atomic precision measurement sensor. For example, the CPT rubidium atomic clock is based on the atomic gas chamber for measurement and can output a highly stable frequency signal. However, when used under conditions where the external ambient temperature changes significantly, the output frequency of the CPT rubidium atomic clock will be affected. The main reason is that the ambient temperature of the atoms in the atomic gas chamber has changed. The temperature change causes the atomic energy level to move, which in turn affects the output frequency of the atomic clock. At present, there are limitations in improving the working temperature stability of the atomic gas chamber by optimizing the physical packaging design and temperature control capabilities. Most methods to reduce the temperature sensitivity of the atomic gas chamber focus on obtaining the temperature frequency shift coefficient and optimizing the buffer gas ratio through theoretical calculation and experiment. The core principle is that the energy level of alkali metal atoms will move with temperature changes due to collisions with buffer gas atoms, but the collision frequency shift coefficients of different buffer gases are different, some of which show positive frequency shifts and some show negative frequency shifts. Therefore, the temperature frequency shift can be offset by filling a certain proportion of buffer gas combination into the atomic gas chamber, and a gas chamber with zero temperature sensitivity at a specific temperature can be constructed. However, as the atomic gas chamber is completed, the buffer gas composition inside it has been determined. In order to achieve the effect of zero temperature sensitivity, the atomic gas chamber can only work at a single working temperature point that has been determined during the design, which does not have flexibility in use; moreover, during the preparation process of the atomic gas chamber, various factors may cause the final performance to deviate from the preset, resulting in the actual applicable working temperature of the formed atomic gas chamber being inconsistent with the preset working temperature, which leads to scrapping, increasing manufacturing costs and reducing production efficiency. Summary of the invention

[0003] Based on the above, the purpose of the present invention is to provide an atomic clock with adjustable working temperature and a preparation method, which has a wide range of applications and good practicality and flexibility of use.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] An atomic clock with adjustable working temperature comprises a packaging shell and a laser source, a light intensity regulating component, an atomic gas chamber, a temperature control component, a detection component and a frequency locking component arranged in the packaging shell, wherein the laser source is used to generate laser light, the light intensity regulating component is arranged between the laser source and the atomic gas chamber, the light intensity regulating component is used to adjust the laser light intensity before the laser is incident into the atomic gas chamber, the atomic gas chamber comprises a transparent glass bulb and an alkali metal and a background gas filled in the transparent glass bulb, the temperature control component is arranged outside the atomic gas chamber and is used to heat and maintain the atomic gas chamber to a preset temperature, the preset temperature is adjustable, the detection component is used to detect the light intensity and output frequency of the laser after passing through the atomic gas chamber, and the frequency locking module is used to control the laser frequency emitted by the laser source according to the detection signal of the detection component.

[0006] As a preferred solution for an atomic clock with adjustable working temperature, the light intensity regulating component includes a half glass plate, a polarizer and a quarter glass plate which are arranged in sequence between the laser source and the atomic gas chamber; the half glass plate is rotatable around its central axis and is arranged in the packaging shell; the polarizer and the quarter glass plate are fixed in the packaging shell.

[0007] As a preferred solution of the atomic clock with adjustable working temperature, it also includes a magnetic shielding component, which is arranged outside the atomic gas chamber and is used to shield the earth's magnetic field.

[0008] As a preferred solution for an atomic clock with adjustable working temperature, it also includes a control module, the temperature control component is electrically connected to the control module, and the control module is used to control the heating temperature of the temperature control component; or the temperature control component is detachably connected to the outside of the atomic gas chamber.

[0009] A method for preparing an atomic clock with adjustable working temperature as described in any of the above technical solutions comprises:

[0010] Preparing an atomic gas chamber, and arranging a temperature-adjustable temperature control component outside the atomic gas chamber;

[0011] Prepare a laser, a light intensity regulating component, a detection component and a frequency locking component, wherein the laser light intensity generated by the laser is known;

[0012] The laser, the light intensity regulating component, the temperature control component and the detection component are used to detect the temperature sensitivity characteristics of the atomic gas chamber under different light intensities of lasers, and obtain the corresponding relationship between the laser light intensity and the zero temperature drift point of the atomic gas chamber;

[0013] The laser, the light intensity regulating component, the atomic gas chamber, the detection component and the frequency locking component are assembled into a packaging shell according to a preset assembly position, and according to the required operating temperature of the atomic clock, the operating temperature of the temperature control component is set or reset to the required operating temperature, and the light intensity regulating component is adjusted to a first adjustment amount according to the required operating temperature and the correspondence between the laser light intensity and the zero temperature drift point of the atomic gas chamber.

[0014] As a preferred solution of a method for preparing an atomic clock with adjustable working temperature, preparing an atomic gas chamber comprises:

[0015] Referring to the correspondence between the background gas filling amount and the working temperature, a preset amount of background gas is filled into the atomic gas chamber packaging chamber according to the required working temperature to obtain the atomic gas chamber.

[0016] As a preferred solution of the method for preparing an atomic clock with adjustable working temperature, the method further includes obtaining the corresponding relationship between the adjustment amount of the light intensity adjustment component and the zero temperature drift point of the atomic gas chamber, which specifically includes the following steps:

[0017] Obtaining a corresponding relationship between an adjustment amount of the light intensity adjustment component and the laser light intensity incident on the atomic gas chamber;

[0018] The laser is used to generate laser light, and the light intensity regulating component is used to change the laser light intensity incident on the atomic gas chamber, and the detection component is used to detect the temperature sensitivity characteristics of the atomic gas chamber under different incident laser light intensities to obtain the temperature sensitivity characteristic curves of the atomic gas chamber under different light intensity lasers;

[0019] According to the temperature sensitivity characteristic curve of the atomic gas chamber under different laser intensities, the corresponding relationship between the laser intensity and the zero temperature drift point of the atomic gas chamber is obtained;

[0020] The correspondence between the adjustment amount and the laser light intensity and the correspondence between the laser light intensity and the zero temperature drift point of the atomic gas chamber is obtained. When adjusting the first adjustment amount, it is adjusted according to the required operating temperature and the correspondence between the adjustment amount and the zero temperature drift point of the atomic gas chamber.

[0021] As a preferred solution of a method for preparing an atomic clock with adjustable working temperature, the light intensity regulating component comprises a half glass plate, a polarizing plate and a quarter glass plate which are arranged in sequence and spaced apart from each other. When assembling the light intensity regulating component, the polarizing plate and the quarter glass plate are fixed in the packaging shell, and the half glass plate is rotated around its central axis and assembled between the polarizing plate and the quarter glass plate.

[0022] Using the light intensity regulating component to change the laser light intensity incident on the atomic gas chamber comprises:

[0023] Each time the half glass slide is rotated by a preset angle, the intensity of the laser light before entering the atomic gas chamber is adjusted to a preset value.

[0024] As a preferred solution of a method for preparing an atomic clock with adjustable working temperature, obtaining the corresponding relationship between the adjustment amount of the light intensity adjustment component and the laser light intensity incident on the atomic gas chamber includes:

[0025] Rotate the half glass slide to the zero adjustment position so that the light intensity of the laser generated by the laser remains unchanged after passing through the light intensity regulating component, and detect and record the transmitted light intensity of the atomic gas chamber through the detection component;

[0026] The half slide is rotated in sequence at a preset angle, and the transmitted light intensity of the atomic gas chamber is detected and recorded by the detection component each time.

[0027] As a preferred solution of a method for preparing an atomic clock with adjustable working temperature, using the detection component to detect the temperature sensitivity characteristics of the atomic gas chamber under different incident laser light intensities includes:

[0028] The light intensity regulating component is adjusted until the laser light intensity before entering the atomic gas chamber is a first light intensity, and within a preset temperature range, the temperature condition of the atomic gas chamber is changed multiple times by the temperature control component, and the corresponding output frequency under each temperature condition is detected and recorded by the detection component to obtain a temperature sensitivity characteristic curve of the atomic gas chamber under the first light intensity;

[0029] Within a preset light intensity range, the light intensity regulating component is adjusted multiple times to the laser light intensity before entering the atomic gas chamber, and the above steps are repeated to obtain temperature sensitivity characteristic curves of the atomic gas chamber under several different laser light intensities.

[0030] The beneficial effects of the present invention are:

[0031] The present invention provides an atomic clock with adjustable working temperature. Since the applicable working temperature of the atomic gas chamber after packaging is determined, the intensity of the laser incident on the atomic gas chamber can be adjusted according to demand by setting a light intensity regulating component. At the same time, by adjusting the working temperature of the temperature control component, the applicable temperature of the atomic clock can be controlled to change according to demand, and the atomic gas chamber is ensured to be in a zero temperature sensitivity characteristic, so as to ensure that the atomic clock outputs a stable frequency. That is, the applicable temperature range of the atomic clock is large, not limited to a single working temperature, and the flexibility of use is better, so that the atomic clock can be applied to more application scenarios.

[0032] The present invention also provides a method for preparing an atomic clock with adjustable working temperature. By detecting the temperature sensitivity characteristics of the atomic gas chamber under different laser light intensities and assembling a light intensity regulating component, even if the applicable working temperature of the used atomic gas chamber is different from the required working temperature of the atomic clock, the use temperature of the atomic clock can be calibrated to the required working temperature through the light intensity regulating component, which is beneficial to saving production costs and improving production efficiency; and when the required working temperature of the atomic clock changes, the applicable temperature of the atomic clock can also be adjusted through the light intensity regulating component and adjusting the working temperature of the temperature control component, so that the applicable temperature range of the atomic clock is wider, and the flexibility and practicality of use are better. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0034] Figure 1 It is a schematic diagram of the structure of an atomic clock with adjustable working temperature provided by an embodiment of the present invention;

[0035] Figure 2 It is a flow chart of a method for preparing an atomic clock with adjustable working temperature provided by an embodiment of the present invention;

[0036] Figure 3 is a temperature sensitivity characteristic curve diagram of the atomic gas chamber under different laser light intensities provided by an embodiment of the present invention;

[0037] Figure 4 is a corresponding relationship diagram of different laser light intensities and zero temperature drift points of the atomic gas chamber provided by an embodiment of the present invention;

[0038] Figure 5 It is a corresponding relationship diagram between the adjustment amount of the light intensity adjustment component and the laser light intensity provided in an embodiment of the present invention.

[0039] In the figure:

[0040] 1. Laser source; 2. Light intensity regulating component; 21. Half glass slide; 22. Polarizer; 23. Quarter glass slide; 3. Atomic gas chamber; 4. Temperature control component; 5. Magnetic shielding component; 6. Detection component; 7. Frequency locking module. DETAILED DESCRIPTION

[0041] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0042] In the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "plurality" means two or more.

[0043] The term "at least one" in this application means one or more, and the term "multiple" in this application means two or more, for example, multiple second messages means two or more second messages. The terms "system" and "network" are often used interchangeably herein.

[0044] It should be understood that the terms used in the description of the various examples herein are only for describing specific examples and are not intended to be limiting. As used in the description of the various examples and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0045] It should also be understood that the term "and / or" used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. The term "and / or" is a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0046] It should also be understood that in the various embodiments of the present application, the size of the serial number of each process does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0047] It should be understood that determining B based on A does not mean determining B only based on A. B can also be determined based on A and / or other information.

[0048] It should also be understood that the term “comprise” (also known as “includes,” “including,” “comprises” and / or “comprising”) when used in this specification specifies the presence of stated features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0049] It should also be understood that the term "if" may be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting." Similarly, the phrase "if it is determined that ..." or "if [a stated condition or event] is detected" may be interpreted to mean "upon determining that ..." or "in response to determining that ..." or "upon detecting [a stated condition or event]" or "in response to detecting [a stated condition or event]," depending on the context.

[0050] It should be understood that the references to "one embodiment", "an embodiment", or "a possible implementation" throughout the specification mean that specific features, structures, or characteristics related to the embodiment or implementation are included in at least one embodiment of the present application. Therefore, the references to "in one embodiment" or "in an embodiment", or "a possible implementation" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0051] like Figure 1As shown, this embodiment provides an atomic clock with adjustable working temperature, which includes a packaging shell and a laser source, a light intensity regulating component, an atomic gas chamber, a temperature control component, a detection component and a frequency locking module arranged in the packaging shell, wherein the laser source is used to generate laser light, the light intensity regulating component is arranged between the laser source and the atomic gas chamber, the light intensity regulating component is used to adjust the laser light intensity before the laser enters the atomic gas chamber, the atomic gas chamber includes a transparent glass bulb and an alkali metal and a background gas filled in the transparent glass bulb, the temperature control component is arranged outside the atomic gas chamber, and is used to heat and maintain the atomic gas chamber to a preset temperature, and the preset temperature is adjustable, the detection component is used to detect the light intensity of the laser after passing through the atomic gas chamber, and the frequency locking module is used to control the laser emission frequency of the laser according to the detection signal of the detection component, so that the atomic clock can work stably. Among them, the laser source is a laser, such as a VCSEL laser, which has the functions of low threshold current, single longitudinal mode operation, circular spot output, high modulation bandwidth, etc.; the detection component is a photodetector. The laser source emits a laser with an oscillation amplitude. The laser passes through a light intensity regulating component. The laser light intensity changes or remains unchanged compared to the laser light intensity emitted by the laser. Then, it enters the atomic gas chamber and interacts with the alkali metal atoms in the atomic gas chamber. The detection component detects the transmitted light intensity of the atomic gas chamber. The frequency locking module demodulates and obtains the frequency error signal between the laser modulation frequency and the atomic transition, thereby locking the laser modulation frequency to the atomic transition frequency, and outputting it as the frequency of the atomic clock. Among them, the atomic gas chamber is, for example, a rubidium atomic gas chamber. Since the applicable working temperature of the atomic gas chamber after packaging is determined, by setting a light intensity regulating component, the laser light intensity incident on the atomic gas chamber can be adjusted according to demand. At the same time, by adjusting the working temperature of the temperature control component, the applicable temperature of the atomic clock can be controlled to change according to demand, and the atomic gas chamber is ensured to be in a zero temperature sensitive characteristic to ensure that the atomic clock outputs a stable frequency. That is, the applicable temperature of the atomic clock is adjustable, not limited to a single working temperature, and the flexibility of use is better, so that the atomic clock can be applied to more application scenarios.

[0052] It should be noted that adjusting the laser intensity incident on the atomic gas chamber by the light intensity regulating component will not affect other characteristics of the laser, and avoids the situation that the frequency may be unstable due to directly adjusting the emission laser intensity by the laser. In this embodiment, the adjustment accuracy of adjusting the laser intensity by the light intensity regulating component is relatively high, so that the working stability of the atomic clock with adjustable working temperature is better.

[0053] Specifically, the frequency locking module is mainly composed of a local oscillator and a control chip. The control chip locks the local oscillator based on the discrimination spectrum of the laser, controls the local oscillator to generate a stable 3.4GHz microwave signal, and loads it onto the laser. At the same time, the microwave signal is used as the frequency output of the atomic clock. Since the frequency locking module is a relatively mature existing technology, it will not be described in detail here.

[0054] Among them, when the atomic clock needs to be used under a certain temperature condition, the control program of the temperature control module is burned so that the working temperature of the temperature control module is the required temperature; when the atomic clock needs to be used under another temperature condition, the control program of the temperature control component is rewritten so that the working temperature of the temperature control module is changed to the required temperature. For example, the atomic clock also includes a control module, and the temperature control component is electrically connected to the control module. The control module is used to control the heating temperature of the temperature control component. The setting of the working temperature of the temperature control component can be achieved by programming the control module. Alternatively, when the atomic clock needs to be used under another temperature condition, the original temperature control component is disassembled, another temperature control component is reassembled, and the working temperature of the temperature control component is set to the required temperature. That is, the temperature control component is detachably connected outside the atomic gas chamber, for example, the temperature control component is a heating coil wound outside the atomic gas chamber.

[0055] Preferably, the atomic clock with adjustable working temperature further comprises a magnetic shielding component, which is arranged outside the atomic gas chamber to shield the earth's magnetic field. For example, a magnetic shielding coil is wound outside the atomic gas chamber to ensure the frequency output stability of the atomic clock.

[0056] In this embodiment, the light intensity regulating component includes a half glass plate, a polarizing plate and a quarter glass plate which are sequentially arranged between the laser source and the atomic gas chamber, the half glass plate is arranged to rotate around its central axis in the packaging shell, and the polarizing plate and the quarter glass plate are fixed in the packaging shell. The laser emitted by the laser source passes through the half glass plate, the polarizing plate and the quarter glass plate in sequence before entering the atomic gas chamber. The combination of the half glass plate and the polarizing plate can regulate the light intensity of the laser emitted by the laser source. The laser passing through the half glass plate is polarized. The polarizing plate corrects the polarization direction of the laser before entering the quarter glass plate. The quarter glass plate is used to convert the polarization state of the laser into circular polarization, so that the polarization state of the laser before entering the atomic gas chamber is circular polarization. The different angles of rotation of the half-glass slide result in different degrees of control over the laser light intensity, which means that the light intensity of the laser before entering the atomic gas chamber is different, thereby adjusting the light intensity of the laser entering the atomic gas chamber, and then comprehensively adjusting the background gas collision frequency shift and the optical frequency shift in the atomic gas chamber, thereby adjusting the suitable working temperature of the atomic gas chamber, which means that the operating temperature of the atomic clock can be adjusted within a certain range, and the atomic gas chamber is in a zero temperature sensitive characteristic state, and the atomic clock has a stable output frequency. The light intensity regulating component has a simple structure, low cost, and small size, and is easy to integrate into a variety of atomic clock systems. Of course, in other embodiments, the light intensity regulating component can also be other structures, such as the light intensity regulating component is an attenuation plate, a liquid crystal, and an acousto-optic modulation crystal.

[0057] Exemplarily, the maximum laser light intensity provided by the laser is 180 μW, and the range of the laser light intensity incident on the atomic gas cell is adjusted to 20 μW-180 μW by the light intensity regulating component.

[0058] The atomic clock with adjustable operating temperature is further illustrated by a specific example. For example, the atomic clock is preset to operate at an operating temperature of 60°C. After the atomic gas chamber is prepared according to the preset operating temperature and the atomic clock is packaged, if the operating temperature of the atomic clock needs to be changed, for example, if it needs to operate at 65°C to meet different application requirements, the operating temperature of the temperature control component is changed, such as rewriting the control program or replacing the temperature control component so that the operating temperature of the temperature control component is 65°C, and the light intensity regulating component is adjusted, such as rotating the angle of the half glass slide, so that the laser intensity incident on the atomic gas chamber changes to the laser intensity corresponding to the zero temperature drift point of the atomic gas chamber of 65°C, so that the atomic clock can output a stable frequency at an operating temperature of 65°C.

[0059] It should be noted that the adjustment amount of the light intensity regulating component, for example, the correspondence between the rotation angle of the half glass slide and the laser intensity of the incident atomic gas chamber is known, and the correspondence between the laser intensity and the zero temperature drift point of the atomic gas chamber is also known. For example, the above-mentioned correspondence is obtained by detection when preparing the atomic clock. When in use, the adjustment amount of the light intensity regulating component is adjusted according to the known correspondence, so as to quickly realize the adjustment of the working temperature of the atomic clock.

[0060] like Figures 2 to 5 As shown, this embodiment also provides a method for preparing an atomic clock with adjustable working temperature, which is used to prepare the above-mentioned atomic clock with adjustable working temperature. The preparation method comprises the following steps:

[0061] S1: prepare an atomic gas chamber and set a temperature-adjustable temperature control component outside the atomic gas chamber;

[0062] Among them, when preparing the atomic gas chamber, refer to the correspondence between the background gas filling amount and the operating temperature, and fill a preset amount of background gas into the atomic gas chamber packaging chamber according to the required operating temperature to obtain the atomic gas chamber. It should be noted that the correspondence between the background gas filling amount and the operating temperature is a prior art, and the details are not repeated here. By filling a preset amount of background gas, the atomic gas chamber has a zero temperature sensitivity characteristic at the corresponding temperature, that is, the preset required operating temperature, so that the prepared atomic clock has a relatively stable output frequency.

[0063] The temperature control component may be a heating coil, which is wound outside the atomic gas chamber, and the working temperature of the atomic gas chamber is controlled by controlling the heating temperature of the heating coil. Exemplarily, the temperature control component controls the working temperature through a control module, and specifically controls the working temperature of the temperature control component through a control program of the control module.

[0064] S2: prepare a laser, a light intensity regulating component, a detection component and a frequency locking component, and the laser light intensity generated by the laser is known;

[0065] The laser, for example, a VCSEL laser, has the functions of low threshold current, single longitudinal mode operation, circular spot output, high modulation bandwidth, etc. The maximum laser light intensity it provides is 180 μW.

[0066] The detection component is, for example, a photodetector.

[0067] The light intensity regulating component is used to regulate the intensity of the laser light emitted by the laser, that is, to regulate the intensity of the laser light incident on the atomic gas chamber, for example, the regulating range is 20 μW-180 μW.

[0068] S3: Using lasers, light intensity regulating components, temperature control components and detection components to detect the temperature sensitivity characteristics of the atomic gas chamber under different light intensities of lasers, and obtain the corresponding relationship between the laser intensity and the zero temperature drift point of the atomic gas chamber;

[0069] Specifically, step S3 includes:

[0070] S31: placing a light intensity adjustment component between the laser and the atomic gas chamber, aligning the detection component with the atomic gas chamber, adjusting the light intensity adjustment component until the laser light intensity before entering the atomic gas chamber is a first light intensity, changing the temperature condition of the atomic gas chamber multiple times within a preset temperature range through the temperature control component, using the detection component to detect and record the output frequency corresponding to each temperature condition, and obtaining a temperature sensitivity characteristic curve of the atomic gas chamber under the first light intensity;

[0071] Exemplarily, the preset temperature range is, for example, 40° C.-70° C., and the output frequency is detected and recorded at intervals of, for example, 5° C. Of course, in other embodiments, the preset temperature range may also be other, which is not limited here.

[0072] S32: Within a preset light intensity range, the light intensity regulating component is adjusted multiple times to the laser light intensity before entering the atomic gas cell, and the above steps are repeated to obtain temperature sensitivity characteristic curves of the atomic gas cell under several different laser light intensities.

[0073] For example, the adjustment amount of the light intensity adjustment component is adjusted multiple times, for example, the laser light intensity incident on the atomic gas chamber is adjusted from 180μW to 20μW per interval of preset light intensity, for example, 50μW per interval, and at each laser light intensity, the temperature within the preset range is adjusted by the temperature control component, and the output frequency is detected and recorded by the detection component each time, so that the temperature sensitivity characteristic curve of the atomic gas chamber at each laser light intensity can be obtained. Figure 3 As shown, the temperature sensitivity characteristic curves of the atomic gas chamber under 30μW and 120μW laser intensities are shown.

[0074] The zero temperature drift point of the atomic gas cell corresponding to each laser intensity can be obtained from the temperature sensitivity characteristic curve of the atomic gas cell under different laser intensities, for example Figure 4As shown, at each laser light intensity, the atomic gas chamber has a corresponding optimal operating temperature, so that the output frequency of the atomic clock made based on this atomic gas chamber is relatively stable and reliable when working at the optimal operating temperature.

[0075] S4: Assemble the laser, light intensity regulating component, atomic gas chamber, detection component and frequency locking component into the packaging shell according to the preset assembly position, set or reset the working temperature of the temperature control component to the required working temperature according to the required working temperature of the atomic clock, and adjust the light intensity regulating component to the first adjustment amount according to the required working temperature and the corresponding relationship between the laser light intensity and the zero temperature drift point of the atomic gas chamber.

[0076] Among them, the frequency locking module is used to control the frequency of the laser emitted by the laser according to the detection signal of the detection component so that the atomic clock can work stably, that is, the laser source emits a laser with an oscillation amplitude, and the laser passes through the light intensity regulation component. The laser light intensity changes or remains unchanged compared with the laser light intensity emitted by the laser, and then enters the atomic gas chamber and interacts with the alkali metal atoms in the atomic gas chamber. The detection component detects the transmitted light intensity of the atomic gas chamber, and the frequency locking module demodulates it to obtain the frequency error signal between the laser modulation frequency and the atomic transition, thereby locking the laser modulation frequency to the atomic transition frequency, and at the same time serving as the frequency output of the atomic clock.

[0077] It should be noted that the temperature control component and the light intensity adjustment component may be set before or after being assembled to the packaging shell.

[0078] For example, if an atomic clock is to be prepared according to a preset required operating temperature, the atomic gas chamber is prepared according to the preset required operating temperature. When preparing the atomic gas chamber, due to limitations of the manufacturing process or conditions, the zero temperature drift point of the atomic gas chamber after packaging may be offset, resulting in its actual applicable operating temperature failing to reach the preset required operating temperature, affecting the output frequency stability of the atomic clock. By testing the temperature sensitivity characteristics of the packaged atomic gas chamber and calibrating the zero temperature drift point of the packaged atomic gas chamber in combination with the light intensity regulation component, there is no need to scrap the atomic gas chamber, so that the final atomic clock can have higher frequency stability. For example, the preset required working temperature of the atomic clock to be manufactured is t1, and the atomic gas chamber is manufactured by filling the background gas with the corresponding amount according to t1, and then the temperature sensitive characteristics of the atomic gas chamber are detected to obtain the zero temperature drift point t2 of the atomic gas chamber, and t2 is compared with t1. If t2 is equal to t1, it means that the atomic gas chamber meets the preset required working temperature, and the light intensity regulating component can be adjusted to the zero adjustment position, that is, the light intensity regulating component does not work, and the working temperature of the temperature control component is set to the preset required working temperature, and then the laser, the light intensity regulating component, the atomic gas chamber and the detection The measuring component is assembled into the packaging shell; if t2 is not equal to t1, it means that the atomic gas chamber does not meet the preset required working temperature. According to the temperature sensitivity characteristic curve of the atomic gas chamber under different laser light intensities, the laser light intensity p1 corresponding to the preset required working temperature t1 is selected, and the light intensity regulating component is adjusted to the laser light intensity incident on the atomic gas chamber to p1, so that the zero temperature drift point of the atomic gas chamber is the preset required working temperature, and the working temperature of the temperature control component is set to the preset required working temperature, and then the laser, light intensity regulating component, atomic gas chamber and detection component are assembled into the packaging shell. The assembled atomic clock has a stable output frequency at the preset required working temperature.

[0079] After the atomic clock is prepared according to the preset required working temperature, if the working temperature of the atomic clock is to be changed, the working temperature of the temperature control component is reset and the light intensity regulation component is adjusted so that the atomic clock can still have a stable output frequency at the changed working temperature. For example, if the changed working temperature is t3, according to the temperature sensitivity characteristic curve of the atomic gas chamber under different laser light intensities, the light intensity regulation component is adjusted so that the zero temperature drift point of the atomic gas chamber is t3, and the working temperature of the temperature control component is reset to t3, that is, the atomic clock can still have a stable output frequency at the temperature of t3.

[0080] In order to facilitate accurate and rapid adjustment of the light intensity adjustment component to the required adjustment amount, the preparation method also includes obtaining the corresponding relationship between the adjustment amount of the light intensity adjustment component and the zero temperature drift point of the atomic gas chamber, specifically including the following steps:

[0081] S21: obtaining a corresponding relationship between an adjustment amount of the light intensity adjustment component and the laser light intensity incident on the atomic gas chamber;

[0082] Specifically, the light intensity modulation component includes a half glass plate, a polarizing plate and a quarter glass plate which are arranged in sequence. When assembling the light intensity modulation component, the polarizing plate and the quarter glass plate are fixed in the packaging shell, and the half glass plate is rotated around its central axis and assembled between the polarizing plate and the quarter glass plate. Of course, in other embodiments, the light intensity modulation component can also be other structures, such as an attenuation plate, liquid crystal, acousto-optic modulation crystal, etc.

[0083] In this embodiment, when obtaining the corresponding relationship between the adjustment amount of the light intensity adjustment component and the laser light intensity incident on the atomic gas chamber, the light intensity adjustment component is placed between the laser and the atomic gas chamber, and the half glass slide is rotated to the zero adjustment position so that the light intensity of the laser generated by the laser remains unchanged after passing through the light intensity adjustment component, and the transmitted light intensity of the atomic gas chamber is detected and recorded by the detection component; the half glass slide is rotated at a preset angle in sequence, for example, the preset angle of each rotation of the half glass slide is 10°, and the transmitted light intensity of the atomic gas chamber is detected and recorded by the detection component each time, so as to obtain the corresponding relationship between the adjustment amount of the light intensity adjustment component and the laser light intensity. For example, Figure 5 As shown, each time the half glass slide is rotated 10°, the normalized laser intensity is detected. For example, when the rotation angle of the half glass slide is 0, the normalized laser intensity is 1, that is, the laser intensity does not attenuate after passing through the half glass slide. After rotating the half glass slide multiple times and detecting, the corresponding relationship between the adjustment amount of the light intensity regulating component and the laser intensity incident on the atomic gas chamber can be obtained.

[0084] S22: using a laser to generate laser light, using a light intensity regulating component to change the laser light intensity incident on the atomic gas chamber, using a detection component to detect the temperature sensitivity characteristics of the atomic gas chamber under different incident laser light intensities, and obtaining the temperature sensitivity characteristic curves of the atomic gas chamber under different light intensity lasers;

[0085] Specifically, half of the glass slide is rotated at a preset angle at every interval from 0 to achieve multiple changes in laser intensity. Then, under each laser intensity condition, the temperature condition is changed multiple times by the temperature control component, and the output frequency is detected and recorded by the detection component to obtain the temperature sensitivity characteristic curve of the atomic gas chamber under each laser intensity.

[0086] S23: Obtaining the corresponding relationship between the laser intensity and the zero temperature drift point of the atomic gas chamber according to the temperature sensitivity characteristic curve of the atomic gas chamber under different laser intensities;

[0087] That is, the peak value of each temperature-sensitive characteristic curve is the zero temperature drift point of the atomic gas chamber under the corresponding laser intensity.

[0088] S24: Obtain the correspondence between the adjustment amount and the zero temperature drift point of the atomic gas chamber according to the correspondence between the adjustment amount and the laser light intensity and the correspondence between the laser light intensity and the zero temperature drift point of the atomic gas chamber. When adjusting the first adjustment amount, adjust it according to the required operating temperature and the correspondence between the adjustment amount and the zero temperature drift point of the atomic gas chamber.

[0089] For example, the laser intensity corresponding to the adjustment amount of 0 is p0, and the peak value of the atomic gas chamber temperature sensitivity characteristic curve detected under the condition of p0 is t0, then the zero temperature drift point corresponding to the adjustment amount of 0 is t0, the laser intensity corresponding to the adjustment amount of 10° is p1, and the peak value of the atomic gas chamber temperature sensitivity characteristic curve detected under the condition of p1 is t1, then the zero temperature drift point corresponding to the adjustment amount of 10° is t1, and so on, the corresponding relationship between the adjustment amount and the zero temperature drift point of the atomic gas chamber is obtained. When packaging an atomic clock or changing the operating temperature of an atomic clock, the light intensity adjustment component can be quickly and accurately adjusted according to the corresponding relationship between the adjustment amount and the zero temperature drift point of the atomic gas chamber.

[0090] The method for preparing an atomic clock with adjustable working temperature provided in this embodiment detects the temperature sensitivity characteristics of the atomic gas chamber under different laser light intensities and assembles a light intensity regulating component. Even if the applicable working temperature of the atomic gas chamber used is different from the required working temperature of the atomic clock, the light intensity regulating component can be used to calibrate the working temperature of the atomic clock to the required working temperature, which is beneficial to saving production costs and improving production efficiency. When the required working temperature of the atomic clock changes, the applicable temperature of the atomic clock can also be adjusted by adjusting the working temperature of the light intensity regulating component and the temperature control component, so that the applicable temperature range of the atomic clock is wider and the flexibility and practicality of use are better.

[0091] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An atomic clock with adjustable working temperature, characterized in that: The invention comprises a packaging shell and a laser source, a light intensity regulating component, an atomic gas chamber, a temperature control component, a detection component and a frequency locking module arranged in the packaging shell, wherein the laser source is used to generate laser light, the light intensity regulating component is arranged between the laser source and the atomic gas chamber, the light intensity regulating component is used to adjust the laser light intensity before the laser is incident into the atomic gas chamber, the atomic gas chamber comprises a transparent glass bulb and an alkali metal and a background gas filled in the transparent glass bulb, the temperature control component is arranged outside the atomic gas chamber and is used to heat and maintain the atomic gas chamber to a preset temperature, the preset temperature is adjustable, the detection component is used to detect the light intensity of the laser after passing through the atomic gas chamber, and the frequency locking module is used to control the laser frequency emitted by the laser source according to the detection signal of the detection component.

2. The atomic clock with adjustable working temperature according to claim 1, characterized in that: The light intensity regulating component comprises a half glass plate, a polarizing plate and a quarter glass plate which are sequentially arranged between the laser source and the atomic gas chamber; the half glass plate is arranged in the packaging shell and rotates around its central axis; the polarizing plate and the quarter glass plate are fixed in the packaging shell.

3. The atomic clock with adjustable working temperature according to claim 1, characterized in that: It also includes a magnetic shielding component, which is arranged outside the atomic gas chamber and is used to shield the earth's magnetic field.

4. The atomic clock with adjustable working temperature according to claim 1, characterized in that: It also includes a control module, the temperature control component is electrically connected to the control module, and the control module is used to control the heating temperature of the temperature control component; or the temperature control component is detachably connected outside the atomic gas chamber.

5. A method for preparing an atomic clock with adjustable working temperature as claimed in any one of claims 1 to 4, characterized in that: The preparation method comprises: Preparing an atomic gas chamber, and arranging a temperature-adjustable temperature control component outside the atomic gas chamber; Prepare a laser, a light intensity regulating component, a detection component and a frequency locking component, wherein the laser light intensity generated by the laser is known; The laser, the light intensity regulating component, the temperature control component and the detection component are used to detect the temperature sensitivity characteristics of the atomic gas chamber under different light intensities of lasers, and obtain the corresponding relationship between the laser light intensity and the zero temperature drift point of the atomic gas chamber; The laser, the light intensity regulating component, the atomic gas chamber, the detection component and the frequency locking component are assembled into a packaging shell according to a preset assembly position, and according to the required operating temperature of the atomic clock, the operating temperature of the temperature control component is set or reset to the required operating temperature, and the light intensity regulating component is adjusted to a first adjustment amount according to the required operating temperature and the corresponding relationship between the laser light intensity and the zero temperature drift point of the atomic gas chamber.

6. The method for preparing an atomic clock with adjustable working temperature according to claim 5, characterized in that: Preparing an atomic gas cell involves: Referring to the correspondence between the background gas filling amount and the working temperature, a preset amount of background gas is filled into the atomic gas chamber packaging chamber according to the required working temperature to obtain the atomic gas chamber.

7. The method for preparing an atomic clock with adjustable working temperature according to claim 5, characterized in that: The method further includes obtaining a corresponding relationship between the adjustment amount of the light intensity adjustment component and the zero temperature drift point of the atomic gas chamber, which specifically includes the following steps: Obtaining a corresponding relationship between an adjustment amount of the light intensity adjustment component and the laser light intensity incident on the atomic gas chamber; The laser is used to generate laser light, and the light intensity regulating component is used to change the laser light intensity incident on the atomic gas chamber, and the detection component is used to detect the temperature sensitivity characteristics of the atomic gas chamber under different incident laser light intensities to obtain the temperature sensitivity characteristic curves of the atomic gas chamber under different light intensity lasers; According to the temperature sensitivity characteristic curve of the atomic gas chamber under different laser intensities, the corresponding relationship between the laser intensity and the zero temperature drift point of the atomic gas chamber is obtained; The correspondence between the adjustment amount and the laser light intensity and the correspondence between the laser light intensity and the zero temperature drift point of the atomic gas chamber is obtained. When adjusting the first adjustment amount, it is adjusted according to the required operating temperature and the correspondence between the adjustment amount and the zero temperature drift point of the atomic gas chamber.

8. The method for preparing an atomic clock with adjustable working temperature according to claim 7, characterized in that: The light intensity adjustment component comprises a half glass plate, a polarizing plate and a quarter glass plate which are arranged in sequence and spaced apart from each other. When assembling the light intensity adjustment component, the polarizing plate and the quarter glass plate are fixed in the packaging shell, and the half glass plate is rotated around its central axis and assembled between the polarizing plate and the quarter glass plate. Using the light intensity regulating component to change the laser light intensity incident on the atomic gas chamber comprises: Each time the half glass slide is rotated by a preset angle, the intensity of the laser light before entering the atomic gas chamber is adjusted to a preset value.

9. The method for preparing an atomic clock with adjustable working temperature according to claim 8, characterized in that: Obtaining the corresponding relationship between the adjustment amount of the light intensity adjustment component and the laser light intensity incident on the atomic gas chamber includes: Rotate the half glass slide to the zero adjustment position so that the light intensity of the laser generated by the laser remains unchanged after passing through the light intensity regulating component, and detect and record the transmitted light intensity of the atomic gas chamber through the detection component; The half slide is rotated in sequence at a preset angle, and the transmitted light intensity of the atomic gas chamber is detected and recorded by the detection component each time.

10. The method for preparing an atomic clock with adjustable working temperature according to claim 7, characterized in that: Using the detection component to detect the temperature sensitivity characteristics of the atomic gas chamber under different incident laser light intensity conditions includes: The light intensity regulating component is adjusted until the laser light intensity before entering the atomic gas chamber is a first light intensity, and within a preset temperature range, the temperature condition of the atomic gas chamber is changed multiple times by the temperature control component, and the corresponding output frequency under each temperature condition is detected and recorded by the detection component to obtain a temperature sensitivity characteristic curve of the atomic gas chamber under the first light intensity; Within a preset light intensity range, the light intensity regulating component is adjusted multiple times to the laser light intensity before entering the atomic gas chamber, and the above steps are repeated to obtain temperature sensitivity characteristic curves of the atomic gas chamber under several different laser light intensities.

Images