An atomic cell heating device for a laser frequency stabilization system

Abstract

The application relates to a temperature control circuit, which comprises a field effect tube, a delay circuit and a control circuit, wherein one end of the delay circuit is electrically connected with a voltage source, the other end is electrically connected with the field effect tube; one end of the control circuit is electrically connected with the field effect tube, the other end is grounded; the control circuit is further used for being electrically connected with both ends of a heating resistance wire; the delay circuit is configured to make the field effect tube not be turned on at the moment when the voltage source is closed, and make the field effect tube be turned off after the voltage source is disconnected; and the control circuit is configured to control the voltage between the two ends of the heating resistance wire by reducing the increasing rate of the source-drain current of the field effect tube. The temperature control circuit of the application controls the voltage of the heating resistance wire by reducing the increasing rate of the source-drain current of the field effect tube, thereby realizing the uniform heating of an atomic cell.

Description

Technical Field

[0001] This invention relates to the field of optoelectronics technology, and more specifically to an atomic cell heating device for a laser frequency stabilization system. Background Technology

[0002] Lasers possess high coherence, high brightness, and high directionality, making them widely used in medical, industrial, and aerospace fields. In atomic and molecular optics experiments, the first step in building an optical system is to lock the laser frequency; however, the laser frequency can fluctuate due to vibrations, temperature changes, and current variations.

[0003] To reduce laser frequency jitter, commonly used frequency stabilization methods in experiments include saturated absorption spectroscopy stabilization, wavelength modulation stabilization, modulation spectral stabilization, and modulation-transfer spectral stabilization. Among these, modulation spectral stabilization and modulation-transfer spectral stabilization are external modulation methods. The modulation signal is not directly applied to the laser, thus avoiding the introduction of additional frequency and intensity noise. Furthermore, they exhibit a large error signal slope and minimal background signal influence, achieving the best frequency stabilization effect by stabilizing the laser to around 1 kHz from the lock point. Therefore, they are widely used for laser frequency stabilization in cold atom interferometry experiments.

[0004] The modulation-transfer spectral frequency stabilization method involves passing the laser through an atomic cell containing atoms to obtain a spectral signal. The atomic cell is heated to increase the internal vapor density, thereby increasing the magnitude of the spectral signal. The spectral signal is then sent to the servo circuit of the laser, and the laser servo system outputs a feedback signal to the laser to lock the laser frequency.

[0005] However, in the above methods, the atomic cell is a transparent quartz glass tube with thin walls, which is prone to breakage when the stress is uneven. Generally, programmable temperature controllers and relays or programmable power supplies are used to control the heating process. However, such methods require large instruments and are expensive, which is not conducive to the miniaturization and commercialization of laser frequency locking devices.

[0006] Furthermore, the optical path built in optical experiments should be as small as possible, which is conducive to making full use of space and subsequent maintenance. Therefore, the atomic cell heating device in the optical path should be well insulated, prevented from cracking, and uniformly heated, while also meeting the requirements of miniaturization. Summary of the Invention

[0007] Therefore, the purpose of this invention is to overcome the defects of the prior art and provide an atomic cell heating device for laser frequency stabilization system. The atomic cell heating device used in this invention can heat the atomic cell to 100-130℃ without cracking. Furthermore, its circuit structure is simple, it occupies little space, has good temperature control effect, and has low manufacturing cost. This makes the optical path size of the entire frequency stabilization system small and can be widely used in the fields of cold atom experiments, laser precision measurement, and laser frequency stabilization.

[0008] According to a first aspect of the present invention, an atomic cell heating device for a laser frequency stabilization system is provided, comprising: an atomic cell; a heating resistance wire wound around the outer periphery of the atomic cell; and a temperature control circuit electrically connected to the heating resistance wire. The temperature control circuit includes: a field-effect transistor (FET), a delay circuit, and a control circuit. One end of the delay circuit is electrically connected to a voltage source, and the other end is electrically connected to the FET. One end of the control circuit is electrically connected to the FET, and the other end is grounded. The control circuit is also configured to be electrically connected to both ends of the heating resistance wire. The delay circuit is configured to prevent the FET from being turned on at the instant the voltage source is closed, and to turn the FET off after the voltage source is opened. The control circuit is configured to control the FET to be in the Miller plateau period, thereby controlling the voltage across the heating resistance wire by reducing the rate of increase of the source-drain current of the FET.

[0009] Preferably, the atomic pool heating device further includes a protection circuit, wherein the protection circuit is electrically connected to the delay circuit and the field-effect transistor.

[0010] Preferably, the delay circuit includes: a first capacitor, a second resistor, a fifth resistor, and a diode. The fifth resistor is connected in parallel with the first capacitor between the power supply node and the first node. The second resistor is connected between the first node and ground. The diode is connected between the first node and the control terminal of the field-effect transistor.

[0011] Preferably, the control circuit includes a second capacitor and a fourth resistor. One end of the second capacitor is electrically connected to the field-effect transistor, and the other end is connected to the protection circuit. The fourth resistor is connected between the control terminal of the field-effect transistor and ground.

[0012] Preferably, the protection circuit includes a Zener diode and a first resistor, one end of the first resistor is connected to the control terminal of the field-effect transistor, and the other end is connected to the second capacitor, and the Zener diode is connected between the control terminal of the field-effect transistor and the second node.

[0013] Preferably, in the delay circuit, when the voltage source switch is closed, the second resistor charges the first capacitor to ensure that the field-effect transistor is not turned on at the moment the voltage source is closed; and when the voltage source switch is opened, the first capacitor discharges through the fifth resistor to ensure that the field-effect transistor is turned off after the voltage source is opened.

[0014] Preferably, the protection circuit further includes a Zener diode, which is configured to keep the gate-source voltage of the field-effect transistor within a reasonable range through the Zener diode, so as to protect the field-effect transistor from being broken down by excessive voltage.

[0015] Preferably, the protection circuit further includes a first resistor configured to filter out high-frequency current components to prevent the field-effect transistor from self-oscillating.

[0016] Preferably, the heating resistance wire is wound around the atomic cell in the laser frequency stabilization system, and the two ends of the heating resistance wire are connected to the temperature control circuit. The atomic cell is uniformly heated by the steadily rising voltage across the two ends of the heating resistance wire.

[0017] According to a second aspect of the present invention, the present invention provides an atomic cell heating device, which includes the temperature control circuit described in the present invention for heating a heating resistance wire wound on an atomic cell.

[0018] Compared with the prior art, the advantages of the present invention are: 1. The atomic cell can be heated to a high temperature (up to 100-130℃) without cracking, even with a heating power of tens of watts; 2. The temperature control circuit has a simple structure, occupies little space, has good temperature control effect, and low manufacturing cost; 3. Because the temperature control circuit occupies little space, the entire atomic cell heating device has a small box size of 150mm×70mm×70mm, thus ensuring that the surrounding optical components are not affected when the heating temperature is high. Attached Figure Description

[0019] The embodiments of the present invention will be further described below with reference to the accompanying drawings, wherein:

[0020] Figure 1 This is a structural diagram of a temperature control circuit according to an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the optical path of a laser frequency stabilization system according to an embodiment of the present invention;

[0022] Figure 3 A partial top view of the optical path of a laser frequency stabilization system according to an embodiment of the present invention; and

[0023] Figure 4This is a schematic diagram of an atomic pool heating device according to an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is further described in detail below through specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] As described in the background section, atomic cells are transparent quartz glass tubes with thin walls, making them prone to breakage when heated unevenly. Programmable temperature controllers and relays or programmable power supplies are typically used to control the heating process. However, these methods result in bulky and expensive instruments, hindering the miniaturization and commercialization of laser frequency stabilization systems. Optical paths in experiments should be as small as possible to maximize space utilization and facilitate future maintenance. Therefore, the atomic cell heating device within the optical path must be well-insulated, crack-resistant, and provide uniform heating while also meeting miniaturization requirements.

[0026] To address the aforementioned problems, this invention provides a temperature control circuit. This temperature control circuit ensures that the atomic cell will not crack during heating. Furthermore, the circuit has a simple structure, and by adjusting the resistance value within it, the voltage and heating power across the heating resistance wire can be prevented from abruptly changing. A slow increase in heating power means a slow increase in the heat received by the atomic cell, thereby achieving uniform heating.

[0027] The present invention will now be described in detail with reference to the accompanying drawings.

[0028] Figure 1 A structural diagram of a temperature control circuit according to an embodiment of the present invention is shown, as follows: Figure 1 As shown, the temperature control circuit 100 includes a field-effect transistor H1, a delay circuit, a control circuit, and a protection circuit. One end of the delay circuit is electrically connected to the voltage source V1, and the other end is electrically connected to the field-effect transistor H1. One end of the control circuit is electrically connected to the field-effect transistor H1, and the other end is grounded.

[0029] The control circuit is also used for electrical connection to both ends of the heating resistance wire R3;

[0030] The delay circuit is configured to prevent the field-effect transistor H1 from being turned on when the voltage source V1 is closed, and to turn off the field-effect transistor H1 when the voltage source V1 is opened; and

[0031] The control circuit is configured to control the field-effect transistor to be in the Miller plateau period, thereby controlling the voltage across the heating resistance wire R3 by reducing the rate of increase of the source-drain current of the field-effect transistor H1.

[0032] According to one embodiment of the present invention, the delay circuit includes: a first capacitor C1, a second resistor R2, a fifth resistor R5 and a diode D1, wherein the fifth resistor R5 and the first capacitor C1 are connected in parallel between the power supply node and the first node, the second resistor R2 is connected between the first node and ground, and the diode D1 is connected between the first node and the control terminal of the field-effect transistor H1.

[0033] According to one embodiment of the present invention, the first node is located at the common connection point of the second resistor R2, the first capacitor C1, and the fifth resistor R5, and is also connected to the anode of the diode D1. It is the sampling node of the power supply V1 after voltage division by R5 and R2.

[0034] The delay circuit is equivalent to being connected in parallel between the source and gate of the field-effect transistor H1. When the voltage source V1 is closed, the second resistor R2 charges the first capacitor C1, and the gate-drain voltage of the field-effect transistor H1 slowly increases to the threshold voltage to ensure that the field-effect transistor H1 is not turned on at the moment the voltage source V1 is closed. When the voltage source V1 is opened, the first capacitor C1 discharges through the fifth resistor R5 to ensure that the field-effect transistor H1 can be turned off after the voltage source V1 is opened. That is, the fifth resistor R5 provides a discharge path for the first capacitor C1, and the second resistor R2 provides a discharge path for the second capacitor C2.

[0035] Since the current charges the capacitor, positive and negative charges will exist on the two terminals of the capacitor. When the voltage source V1 is turned off, if there is no discharge channel, the charge on the capacitor cannot be neutralized. At this time, the capacitor will be equivalent to a constant voltage source, and the field-effect transistor will remain on. In this way, when the voltage source V1 is turned off again, the circuit will not work properly. Therefore, it is necessary to discharge to neutralize the charge on the capacitor, so that the voltage difference between the two terminals of the capacitor is zero, and the field-effect transistor H1 is turned off. In this way, the voltage on both sides of the heating resistance wire R3 can change slowly every time the voltage source V1 is turned off and turned off again.

[0036] According to one embodiment of the present invention, the control circuit includes a second capacitor C2 and a fourth resistor R4. One end of the second capacitor C2 is electrically connected to the field-effect transistor H1, and the other end is connected to the protection circuit. The fourth resistor R4 is connected between the control terminal of the field-effect transistor H1 and ground.

[0037] The control circuit is used to control the field-effect transistor H1 to be in the Miller plateau period. The Miller plateau period refers to the period when the manufacturing process of the field-effect transistor introduces parasitic capacitances between the gate and source, gate and drain, and source and drain. When a current is applied to the gate to control the turn-on of the field-effect transistor, the current first charges the parasitic capacitance between the gate and source, causing the gate-source voltage to increase. Once the parasitic capacitance between the gate and source is fully charged, the current charges the gate-drain capacitance, but the gate-source voltage does not continue to increase; instead, it remains essentially constant until the gate-drain capacitance is fully charged. This period of essentially constant gate-source voltage is called the Miller plateau period. When the field-effect transistor is in the Miller plateau period, its source-drain voltage is controlled by the gate-drain voltage. The second capacitor C2 and the fourth resistor R4 cause the gate-drain voltage of the field-effect transistor H1 to change slowly. The rate of change of the voltage is proportional to the product of the second capacitor C2 and the fourth resistor R4. The rate of change of the source-drain current of the field-effect transistor H1 is proportional to the rate of change of the gate-drain voltage of the field-effect transistor H1, thereby controlling the rate of increase of the output current. The two ends of the heating resistance wire are connected to the control circuit, so the voltage on both sides of the heating resistance wire will slowly rise to the voltage source voltage. The rate of rise is determined by the product of the second capacitor C2 and the fourth resistor R4.

[0038] The temperature control circuit adjusts the charging time of the gate-source and gate-drain terminals of the field-effect transistor H1 by regulating the values ​​of the fourth resistor R4 and the second capacitor C2, thereby adjusting the rate of change of the source-drain current and controlling the rise time of the voltage across the heating resistance wire R3. When the voltage source is turned on, for fixed values ​​of the fourth resistor R4 and the second capacitor C2, the slope of the voltage rise across the heating resistance wire is constant. When the value of the second capacitor C2 is fixed, the rise time can be adjusted solely by resistor R4. The resistance of R4 is proportional to the rise time; by changing the value of R4, the rise time can be adjusted from 0 to tens of minutes. For example, when R4 is 2MΩ, the corresponding rise time is 17 minutes. Therefore, it can be seen that the entire circuit structure of this invention is simple, has low power consumption, occupies little space, and the components are readily available.

[0039] According to one embodiment of the present invention, the protection circuit includes a Zener diode D2 and a first resistor R1. One end of the first resistor R1 is connected to the control terminal of the field-effect transistor H1, and the other end is connected to the second capacitor C2. The Zener diode D2 is connected between the control terminal of the field-effect transistor H1 and the second node.

[0040] The second node is located at the common connection point of the cathode of diode D1, the cathode of Zener diode D2, the gate of MOSFET H1, and the upper end of the fourth resistor R4, and is the output node of the control signal.

[0041] Zener diode D2 is used to keep the gate-source voltage of MOSFET H1 within a reasonable range to protect MOSFET H1 from being broken down by excessive voltage; Zener diode D2 is connected in parallel between the source and gate of MOSFET H1, and Zener diode plays the role of protecting MOSFET.

[0042] The first resistor R1 filters out high-frequency current components to prevent the field-effect transistor H1 from oscillating.

[0043] In practical applications, the temperature control circuit described above is made into a printed circuit board, with ports reserved for connecting the voltage source V1 and the heating resistance wire R3. The heating resistance wire R3 is first wound around the atomic cell, and then both ends of the heating resistance wire R3 are connected to the circuit board. The actual voltage source used is... Figure 1 The voltage source on the left is represented in the circuit diagram and is connected to the voltage source input port of the temperature control circuit board.

[0044] Heating resistance wire in Figure 1 In the circuit diagram, R3 represents the voltage across the heating element. After the power is turned on, due to the influence of the temperature control circuit, when, for example, R4 is 2MΩ and C2 is 470uf, the voltage across R3 increases to the power supply voltage at a fixed rate of approximately 20 mV / s (the rate can be adjusted by R4). This prevents abrupt changes in the voltage across the heating resistance wire and the heating power. The slow increase in heating power means that the heat received by the atomic cell also increases slowly, which is beneficial for the full conduction of heat in the atomic cell, thus achieving the purpose of uniform heating. The key to achieving uniform heating lies in the field-effect transistor in the temperature control circuit. The temperature control circuit achieves uniform heating of the atomic cell by reducing the rate of increase of the source-drain current of the field-effect transistor.

[0045] For example, in the operation of the temperature control circuit, the resistance of R5 can be set to 1000 ohms, the resistance of R2 to 9000 ohms, the capacitance of C1 to 15000uF, the capacitance of C2 to 470uF, the model of D1 to be 1N4148, the model of D2 to be 1N8373B, the model of H1 to be HAT1072H, the resistance of R1 to be 100 ohms, the resistance of R4 to be 2M ohms, and the resistance of R3 to be 18 ohms. With the above temperature control circuit, the atomic cell can be heated uniformly without cracking, and the heating temperature can reach 100-130℃.

[0046] According to other embodiments of the present invention, in the temperature control circuit, the P-channel enhancement-mode MOSFET H1, diode D1, and Zener diode D2 can be replaced by the same type of components; the value of R4 can be changed according to the actual required voltage rise rate across the heating resistance wire, and the value of R4 is proportional to the voltage rise rate across the heating resistance wire.

[0047] In some implementations, the temperature control circuit 100 includes a field-effect transistor H1, a delay circuit, and a control circuit. This temperature control circuit may not include a protection circuit; specifically, the temperature control circuit 100 may not include any one or both of the Zener diode D2 and the first resistor R1, yet uniform heating of the atomic cell can still be achieved.

[0048] Figure 3 A schematic diagram of the optical path of a laser frequency stabilization system according to an embodiment of the present invention is shown. The laser frequency stabilization system adopts the temperature control circuit of the present invention. The laser frequency stabilization system includes a laser 110, a first beam splitter M1, a second beam splitter M2, a third beam splitter M3, a fourth beam splitter M4, a fifth beam splitter M5, a sixth beam splitter M6, an atomic cell heating device 150, a temperature control circuit 1501, a signal acquisition device 130, a modulator 120, a demodulation circuit 140, an oscilloscope 160, and a laser servo system 170.

[0049] The signal acquisition device 130 can be a photodetector. When the optical signal to be stabilized emitted by the laser 110 passes through the first beam splitter M1, it is split into reflected light and transmitted light. The transmitted light enters the modulation transfer spectrum frequency stabilization optical path, and the reflected light is used for subsequent optical paths. After passing through the second beam splitter M2, the transmitted light is split into the first probe light and the first saturated light because the polarization directions are different. The first saturated light passes through the third beam splitter M3 and enters the modulator 120. The modulator 120 modulates the phase of the first saturated light. The saturated light modulated by the modulator 120 is the second saturated light, which has one carrier and two sidebands. The distance between the carrier and the sidebands is the modulation frequency, which is generally on the order of MHz.

[0050] After passing through the sixth beam splitter M6, the fifth beam splitter M5, and the fourth beam splitter M4, the second saturated light reaches the atomic pool heating device 150 and coincides with the first probe light propagating in the opposite direction in the atomic pool 1502 of the atomic pool heating device 150. Before the coincidence, the temperature control circuit 1501 of the present invention has already started to control the atomic pool heating device 150 to preheat. Under the influence of a certain temperature and the four-wave mixing effect, the first probe light, the second saturated light and the gaseous atoms in the atomic pool interact with the gaseous atoms in the atomic pool, resulting in the second probe light emitted from the atomic pool also having a carrier wave and two sidebands.

[0051] The atomic pool heating device 150 of the present invention includes: a temperature control circuit 1501, an atomic pool 1502 wound with heating resistance wire, and a housing. The temperature control circuit 1501 is connected to the atomic pool 1502 wound with heating resistance wire R3. The cylindrical atomic pool inside the atomic pool heating device 150 has a diameter of 15-20 mm and a length of 80-110 mm. The housing dimensions of the heating device are 150 mm × 70 mm × 70 mm, and the overall optical path size is small, measuring 400 mm × 230 mm.

[0052] The atomic cell 1502 is heated by heating resistance wires wound around its exterior. The currents in adjacent heating resistance wires are in opposite directions to cancel out the magnetic field caused by the current. The current is generated by voltage source V1, passes through temperature control circuit 1501, and reaches the heating resistance wires. The atomic cell with the heating resistance wires wound around it is then placed in the atomic cell heating device.

[0053] The second probe light is collected by the photodetector after passing through the fourth beam splitter M4. The optical signal output by the photodetector is amplified, mixed, and filtered by the demodulation circuit to obtain the modulation transfer spectrum signal. The modulation transfer spectrum signal is proportional to the difference between the laser frequency emitted by the laser and the reference frequency. The larger the difference, the more unstable the laser frequency emitted by the laser, and vice versa. The demodulation circuit 140 outputs the modulation transfer spectrum signal to the oscilloscope and the laser servo system through a parallel structure.

[0054] An oscilloscope is used to observe the magnitude of the modulation transfer spectrum signal at different heating temperatures. The oscilloscope has a synchronization circuit. As long as the frequency of the signal is within the monitoring range of the oscilloscope, the oscilloscope can automatically synchronize with the frequency of the signal source and repeatedly display the waveform of the signal on the screen. In this way, a stable waveform can be seen and read, that is, the magnitude of the modulation transfer spectrum signal at different heating temperatures can be observed. Then, the heating temperature and voltage at which the modulation transfer spectrum signal reaches its maximum value can be determined, and the position of the modulation transfer spectrum signal can be locked, that is, the lock point position can be determined.

[0055] The laser itself is equipped with a laser servo system (PID controller) and piezoelectric ceramics. The laser servo system outputs a feedback signal to the piezoelectric ceramics, which are located on the resonant cavity of the laser. The length of the piezoelectric ceramics can be varied. By changing the length of the piezoelectric ceramics, the cavity length of the laser is changed. As the cavity length of the laser changes, the frequency of the emitted laser also changes. The feedback signal provides negative feedback to the output laser frequency, which can stabilize and lock the output laser frequency. During the locking process, a signal is also present on the oscilloscope. The oscilloscope displays this signal as a straight line. This line will fluctuate in amplitude. Based on this change, the magnitude of the laser frequency fluctuation can be determined. The smaller and more sustained the fluctuation, the more stable the laser frequency is, and thus, whether the laser frequency has been locked.

[0056] Figure 3 This is a top view of the optical path of a laser frequency stabilization system according to an embodiment of the present invention, as shown below. Figure 3 As shown, the overall dimensions of the laser frequency stabilization system are: length 400mm, width 230mm, and height 150mm. The housing dimensions of the atomic cell heating device of this invention are 150mm long, 70mm wide, and 70mm high; the modulator is self-made, with dimensions of 41mm long, 62mm wide, and 39mm high; the dimensions of the signal acquisition device (such as a photodetector) are not fixed. The small optical path size of this invention is beneficial for making full use of space and for subsequent maintenance.

[0057] Figure 4 An atomic cell heating device 400 according to an embodiment of the present invention includes: a temperature control circuit 410 of the present invention for heating a heating resistance wire wound on an atomic cell.

[0058] The atomic pool heating device 400 of the present invention further includes an atomic pool 420 wound with heating resistance wire and a box 430, wherein the temperature control circuit 410 is located outside the box 430, the atomic pool 420 is located inside the box 430, and the box 430 has heat preservation characteristics.

[0059] In actual use, the atomic cell 420 is placed inside the housing 430. After the resistance wire is wound around the glass wall of the atomic cell, two connectors will extend out through the small holes reserved on the housing 430. The housing 430 is placed on the optical stage, and the temperature control circuit 410 is located on the bracket above the optical stage. The wires on the temperature control circuit 410 will be connected to the two connectors extending out of the housing 430.

[0060] Among them, the columnar atomic cell inside the atomic cell heating device 150 has a diameter of 15-20mm and a length of 80-110mm. The size of the box 430 in the heating device 150 is 150mm×70mm×70mm. The overall optical path size is small, with an optical path size of 400mm×230mm.

[0061] The box body 430 of this invention also has excellent heat insulation properties. The box body 430 consists of two layers: an inner layer made of aluminum alloy and an outer layer made of high-temperature resistant Teflon. The aluminum alloy block is hollowed out in the center to accommodate the atomic cell. The aluminum alloy block is then placed inside the Teflon shell. The aluminum of the inner layer can be other metals, such as copper, pure aluminum, or iron. The outer layer can also be made of materials such as PVC plastic.

[0062] When the temperature of the atomic cell with the heating resistance wire is raised to a constant temperature, and the voltage source V1 is suddenly disconnected, the box 430 will ensure that the temperature difference at various points on the glass wall is small during the cooling process of the atomic cell. There is no situation where the temperature difference at various points is large due to the sudden closing of the power supply. Therefore, due to the heat preservation characteristics of the box 430, it is not necessary to make the voltage on both sides of the heating resistance wire change slowly when the voltage source V1 is disconnected.

[0063] It should be noted that although the steps are described in a specific order above, it does not mean that the steps must be executed in the above specific order. In fact, some of these steps can be executed concurrently, or even in a different order, as long as the required function can be achieved.

[0064] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. An atomic cell heating device for a laser frequency stabilization system, comprising: atomic pool; Heating resistance wire wound around the outer periphery of the atomic cell; Box body; as well as A temperature control circuit electrically connected to the heating resistance wire, wherein the atomic cell is located inside the housing, the temperature control circuit is located outside the housing, the housing has heat insulation properties, and the temperature control circuit includes: Field-effect transistors, delay circuits, and control circuits, among which, One end of the delay circuit is electrically connected to the voltage source, and the other end is electrically connected to the field-effect transistor; one end of the control circuit is electrically connected to the field-effect transistor, and the other end is grounded. The control circuit is also used to electrically connect to both ends of the heating resistance wire; The delay circuit is configured to prevent the field-effect transistor from being turned on at the instant the voltage source is closed, and to turn off the field-effect transistor after the voltage source is opened; and The control circuit is configured to control the field-effect transistor to be in the Miller plateau period, thereby controlling the voltage across the heating resistance wire by reducing the rate of increase of the source-drain current of the field-effect transistor.

2. The atomic cell heating device according to claim 1 further includes a protection circuit, wherein, The protection circuit is electrically connected to the delay circuit and the field-effect transistor.

3. The atomic cell heating device according to claim 1, wherein, The delay circuit includes: a first capacitor, a second resistor, a fifth resistor, and a diode. The fifth resistor is connected in parallel with the first capacitor between the power supply node and the first node. The second resistor is connected between the first node and ground. The diode is connected between the first node and the control terminal of the field-effect transistor.

4. The atomic cell heating apparatus according to any one of claims 1-3, wherein, The control circuit includes a second capacitor and a fourth resistor. One end of the second capacitor is electrically connected to the field-effect transistor, and the other end is connected to the protection circuit. The fourth resistor is connected between the control terminal of the field-effect transistor and ground.

5. The atomic cell heating device according to claim 4, wherein, The protection circuit includes a Zener diode and a first resistor. One end of the first resistor is connected to the control terminal of the field-effect transistor, and the other end is connected to the second capacitor. The Zener diode is connected between the control terminal of the field-effect transistor and the second node.

6. The atomic cell heating device according to claim 3, wherein, In the delay circuit, When the voltage source switch is closed, the second resistor charges the first capacitor to ensure that the field-effect transistor is not turned on at the moment the voltage source is closed. as well as When the voltage source switch is turned off, the first capacitor discharges through the fifth resistor to ensure that the field-effect transistor is turned off after the voltage source is turned off.

7. The atomic cell heating device according to claim 2, wherein, The protection circuit also includes a Zener diode, which is configured to keep the gate-source voltage of the field-effect transistor within a reasonable range to protect the field-effect transistor from being damaged by excessive voltage.

8. The atomic cell heating device according to claim 7, wherein, The protection circuit also includes a first resistor configured to filter out high-frequency current components to prevent the field-effect transistor from self-oscillating.

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