Control device for single-photon sensing device, single-photon detection device, and chip

Abstract

The application discloses a control device of a single-photon sensing device, which comprises a first voltage module, a second voltage module and a single-photon sensing device; the first voltage module is coupled with the single-photon sensing device and is configured to apply a first voltage signal to the single-photon sensing device, wherein the first voltage signal comprises a direct current voltage signal; the second voltage module is coupled with the single-photon sensing device and is configured to apply a second voltage signal to the single-photon sensing device, wherein the second voltage signal comprises a periodically changed voltage signal; and the first voltage signal and the second voltage signal are superimposed to make the single-photon sensing device work alternately in an avalanche region and a cutoff region. The control device of the single-photon sensing device can apply a direct current bias voltage and a gated alternating signal to the single-photon sensing device through the direct current voltage module and the alternating voltage module, so that the single-photon sensing device works alternately in the avalanche region and the cutoff region, and the superimposed signal range of the direct current voltage signal and the gated alternating voltage signal can be effectively controlled.

Description

TECHNICAL FIELD

[0001] The present application relates to the weak light detection technical field, especially to a control device of a single photon sensing device, a single photon detection device comprising the same, a chip integrated with the single photon detection device and a method for controlling the single photon sensing device using the control device. BACKGROUND

[0002] Due to the needs of quantum key distribution, fiber sensing, fiber communication, laser radar, high-energy physics, semiconductor device characteristic analysis and biological imaging, a single photon detection device based on a semiconductor avalanche photodiode (APD) has been widely used,

[0003] Among them, the avalanche photodiode for the fiber communication waveband (1310 nanometers and 1550 nanometers) is mainly based on indium gallium arsenide (InGaAs) material. In order to suppress the after-pulse noise (after current) of the single photon detection device based on the indium gallium arsenide avalanche photodiode and improve the photon counting rate of the single photon detection device, the avalanche photodiode is usually driven by a gate to reduce the avalanche charge and the recovery time after the avalanche.

[0004] A direct current bias voltage is applied to the avalanche photodiode, and then a gate alternating signal is applied, so that the avalanche photodiode works in the avalanche region for a certain time in the gate signal period, and an avalanche current is generated in response to a single photon level incident light signal; and for the remaining time in the gate signal period, the avalanche photodiode works in the linear region or the cutoff region, and has no response to the incident single photon level light signal. Since the bias voltage is reduced, the generation of the after current is suppressed, the dead time of the avalanche photodiode is reduced, and the detection efficiency is improved.

[0005] In order to quickly quench the avalanche current, a gate voltage signal in a reasonable range needs to be provided. In the existing single photon detection scheme based on the avalanche photodiode, the providing end of the gate voltage signal generally adopts a 50-ohm characteristic impedance. In order to achieve a high gate voltage, a large power is generally required, which is not ideal from the safety and economy of signal transmission. SUMMARY

[0006] In view of at least one defect of the prior art, the present application provides a control device of a single photon sensing device, comprising:

[0007] A first voltage module coupled to the single photon sensing device and configured to apply a first voltage signal to the single photon sensing device, the first voltage signal comprising a direct current voltage signal;

[0008] A second voltage module, coupled to the single-photon sensor, is configured to apply a second voltage signal to the single-photon sensor. The second voltage signal includes a periodically changing voltage signal. The first voltage signal is superimposed on the second voltage signal to cause the single-photon sensor to operate alternately in the avalanche region and the cutoff region.

[0009] According to one aspect of the invention, wherein

[0010] When the first voltage signal and the second voltage signal are in the same direction, the absolute value of the superimposed signal of the first voltage signal and the second voltage signal is greater than the first threshold.

[0011] When the first voltage signal is in the opposite direction to the second voltage signal, the absolute value of the superimposed signal of the first voltage signal and the second voltage signal is less than the second threshold.

[0012] According to one aspect of the invention, the second voltage module comprises:

[0013] The signal generation submodule is configured to generate periodically changing voltage signals;

[0014] A signal amplification submodule is coupled to the signal generation submodule and configured to amplify the voltage signal generated by the signal generation submodule.

[0015] According to one aspect of the invention, the signal amplification submodule includes a transformer.

[0016] According to one aspect of the invention, the control device further comprises:

[0017] The control module is coupled to the first voltage module and the second voltage module respectively, and is configured to control the output of the second voltage module according to the first voltage signal.

[0018] According to one aspect of the invention, the control module is further configured to:

[0019] When the first voltage signal is less than the third threshold, the second voltage module is controlled to stop applying the second voltage signal to the single-photon sensor.

[0020] According to one aspect of the present invention, the control module includes:

[0021] A dual-channel relay has a control terminal, a first terminal, a second terminal, and a third terminal. The control terminal is coupled to the first voltage module, the first terminal is coupled to the signal generation submodule, the second terminal is coupled to the signal amplification submodule, and the third terminal is coupled to the load. The dual-channel relay is configured as follows:

[0022] Based on the first voltage signal, control the first terminal to be connected to the second terminal, or the first terminal to be connected to the third terminal.

[0023] According to one aspect of the invention, the control module further comprises:

[0024] An AND gate circuit has a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal is coupled to the first voltage module, the second input terminal is coupled to a DC power supply, and the output terminal is coupled to the control terminal of the dual-channel relay. The AND gate circuit is configured as follows:

[0025] Based on the first voltage signal, a control signal is output to the control terminal of the dual-channel relay.

[0026] According to one aspect of the invention, the single-photon sensing device includes an avalanche photodiode, the transformer includes one or more step-up transformers, and the dual-channel relay includes a single-pole double-throw radio frequency switch.

[0027] The present invention also provides a single-photon detection device, comprising:

[0028] A single-photon sensor is configured to receive optical signals and convert them into electrical signals for output.

[0029] The control device described above is coupled to the single-photon sensor and configured to apply a voltage to the single-photon sensor.

[0030] The present invention also provides a chip including a single-photon detection device as described above integrated thereon.

[0031] The present invention also provides a method for controlling a single-photon sensing device using the control device described above, comprising:

[0032] The first voltage signal is applied to the single-photon sensor through the first voltage module;

[0033] The second voltage signal is applied to the single-photon sensor via the second voltage module.

[0034] According to one aspect of the invention, the method further comprises:

[0035] When the first voltage signal and the second voltage signal are in the same direction, control the first voltage module and / or the second voltage module to make the absolute value of the superimposed signal greater than the first threshold.

[0036] When the first voltage signal is opposite to the second voltage signal, the first voltage module and / or the second voltage module are controlled to make the absolute value of the superimposed signal less than the second threshold.

[0037] According to one aspect of the present invention, the second voltage module includes: a signal generation submodule and a signal amplification submodule, the signal generation submodule being coupled to the signal amplification submodule, the signal amplification submodule including a transformer, and the method further comprising:

[0038] The signal generation submodule generates a periodically changing voltage signal;

[0039] The voltage signal generated by the signal generation submodule is amplified by the signal amplification submodule.

[0040] According to one aspect of the present invention, the control device further includes a control module, the control module being coupled to the first voltage module and the second voltage module respectively, and the method further includes:

[0041] The control module controls the output of the second voltage module according to the first voltage signal.

[0042] According to one aspect of the invention, the method further comprises:

[0043] When the first voltage signal is less than the third threshold, the control module controls the second voltage module to stop applying the second voltage signal to the single-photon sensor.

[0044] According to one aspect of the present invention, the control module further comprises: a dual-channel relay and an AND gate circuit, the dual-channel relay having a control terminal, a first terminal, a second terminal, and a third terminal, wherein the first terminal is coupled to the signal generation submodule, the second terminal is coupled to the signal amplification submodule, and the third terminal is coupled to the load; the AND gate circuit has a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal is coupled to the first voltage module, the second input terminal is coupled to a DC power supply, and the output terminal is coupled to the control terminal of the dual-channel relay; the method further comprises:

[0045] The AND gate circuit outputs a control signal to the control terminal of the dual-channel relay based on the first voltage signal.

[0046] The dual-channel relay controls the first terminal to be connected to the second terminal, or the first terminal to be connected to the third terminal.

[0047] The control device and method for controlling a single-photon sensor provided by this invention apply a DC bias voltage and a gated alternating signal to the single-photon sensor through a DC voltage module and an AC voltage module. This causes the single-photon sensor to operate alternately in the avalanche region and the cutoff region, effectively controlling the superposition range of the DC voltage signal and the periodically changing gated voltage signal. This invention uses one or more step-up transformers to amplify the gated alternating signal, and the characteristic impedance of the transmission line at the gated signal terminal is correspondingly increased, keeping the power consumption essentially constant. Only a relatively low-power AC voltage signal is needed to generate a higher gated alternating signal, which is then applied to the single-photon sensor. This invention also implements a bias protection function through a single-pole double-throw RF switch and its use in conjunction with gate circuits, preventing damage to the single-photon sensor from the amplified gated alternating voltage signal. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings, without exceeding the scope of protection claimed by this application.

[0049] Figure 1 A detection device including an avalanche photodiode and its current-voltage characteristic curves are shown.

[0050] Figure 2 The waveform of the gated voltage signal applied to the avalanche photodiode is shown.

[0051] Figure 3 This illustrates that, under the control of a control device for a single-photon sensor provided in one embodiment of the present invention, the single-photon sensor alternately operates in the avalanche region and the cutoff region;

[0052] Figure 4 A control device for a single-photon sensing device provided in one embodiment of the present invention is shown;

[0053] Figure 5 A control device for a single-photon sensing device provided in one embodiment of the present invention is shown;

[0054] Figure 6 A control device for a single-photon sensing device provided in one embodiment of the present invention is shown;

[0055] Figure 7 A control device for a single-photon sensing device provided in one embodiment of the present invention is shown;

[0056] Figure 8A control device for a single-photon sensing device provided in one embodiment of the present invention is shown;

[0057] Figure 9 A control device for a single-photon sensing device provided in one embodiment of the present invention is shown;

[0058] Figure 10 A single-photon detection device provided by one embodiment of the present invention is shown;

[0059] Figure 11 This invention illustrates a method for controlling a single-photon sensing device according to an embodiment of the present invention. Detailed Implementation

[0060] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0061] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this application. Furthermore, any changes or modifications made by those skilled in the art based on the ideas of this application, and on the specific implementation methods and application scope of this application, are all within the scope of protection of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

[0062] Single-photon detection devices typically use avalanche photodiodes (APDs) as photoelectric sensors. Avalanche photodiodes operate under reverse bias, and their operating curves are shown below. Figure 1 As shown ( Figure 1This diagram illustrates a single-photon detection device including an avalanche photodiode and its operating curves. When no photon is incident, the reverse current is extremely weak, called dark current. When a photon is incident, the carrier pairs (electron-hole pairs) generated by light absorption are separated by the electric field, generating a reverse current called photocurrent. In the linear operating region, i.e., when the reverse bias voltage of the APD is below its breakdown voltage, the photocurrent is proportional to the light intensity; at this time, the APD does not possess single-photon detection capability. However, when the reverse bias voltage of the APD is higher than its breakdown voltage, the carriers generated by absorbing single photons are accelerated to sufficient energy by the electric field, enabling them to ionize through collisions, generating new electron-hole pairs and achieving a continuous carrier multiplication effect (i.e., the avalanche effect), thus generating a detectable macroscopic current signal (avalanche current). Under high reverse bias voltage, the sensitivity of the avalanche photodiode can detect optical signals at the single-photon level, making it suitable for single-photon detection devices required in fields such as quantum key distribution and quantum direct communication.

[0063] Avalanche photodiodes (APDs) exhibit afterpulse noise (afterpulse effect), meaning that after an initial avalanche, a secondary avalanche occurs randomly for a period of time when no photons are incident. Afterpulse noise is a type of detector noise and must be suppressed as much as possible. It is related to the avalanche current. The larger the avalanche current, i.e., the higher the reverse bias voltage of the APD, the more pronounced the afterpulse. To suppress afterpulse, the reverse bias voltage of the APD cannot be set too high, as this will affect the single-photon detection efficiency of the APD. Furthermore, APD-based single-photon detection devices typically introduce a long dead time, meaning that for a considerable period after successfully detecting a single-photon avalanche current signal, photon counting ceases, thus reducing the detection count rate of the single-photon detection device.

[0064] To improve the photon counting rate and detection efficiency of single-photon detection devices, avalanche photodiodes are typically driven using a gate-driven approach. For example... Figure 1 As shown, a DC bias voltage is applied to the avalanche photodiode. Typically, this DC bias voltage is close to the breakdown voltage of the avalanche photodiode, meaning it is set near the boundary between the linear operating region and the avalanche region of the photodiode. When this DC bias voltage is applied to the avalanche photodiode, it is in a critical breakdown state. Based on this, a periodically varying gate voltage signal is applied to the avalanche photodiode. For example... Figure 2 As shown, optionally, the gate voltage signal applied to the avalanche photodiode includes a periodically changing voltage signal, such as a sinusoidal voltage signal, a square wave voltage signal, and a triangular wave voltage signal, etc. Figure 2 The waveforms of two gated voltage signals are shown.

[0065] Because a reverse voltage, superimposed on a DC voltage signal and a periodically changing voltage signal, is applied, the current-voltage characteristic of an avalanche photodiode may switch between three operating regions. For example... Figure 3 As shown, when the superimposed reverse voltage is greater than the breakdown voltage of the avalanche photodiode, the avalanche photodiode operates in the avalanche region; when the superimposed reverse voltage is less than the reverse breakdown voltage of the avalanche photodiode but greater than the linear operating voltage of the avalanche photodiode, the avalanche photodiode operates in the linear region; when the superimposed reverse voltage is less than the linear operating voltage of the avalanche photodiode, the avalanche photodiode operates in the cutoff region.

[0066] Typically, a DC voltage signal is set near the breakdown voltage of the avalanche photodiode, and the operating region of the avalanche photodiode is changed by adjusting the periodically varying voltage signal. By applying a higher gate voltage signal to the avalanche photodiode, it can be made to operate in the avalanche region for a certain period of the gate voltage signal period. Upon receiving a single-photon level optical signal, an avalanche occurs, outputting an avalanche current. During the remaining time of the gate voltage signal period, the reverse voltage applied to the avalanche photodiode is close to zero. Due to the lack of voltage, the avalanche current is rapidly quenched, thus reducing the avalanche charge and the recovery time (dead time) after avalanche. By applying a higher gate voltage signal, the afterpulse effect of the avalanche photodiode is effectively suppressed, improving the photon counting rate and detection efficiency of the single-photon detection device, achieving excellent control results. However, when a high gate voltage signal is applied, the power loss at the gate voltage signal provider and its transmission line also increases. Furthermore, as mentioned earlier, the higher the reverse bias voltage of the avalanche photodiode, the more pronounced the afterpulse effect. To suppress the afterpulse, the reverse bias voltage cannot be set too high. Conversely, if the voltage signal resulting from the superposition of the DC voltage signal and the gate voltage signal is a forward voltage signal exceeding a certain value, it may cause the avalanche photodiode to conduct in the forward direction, resulting in damage. Therefore, a control device and method are needed that can save power while effectively controlling the superposition range of the DC voltage signal and the periodically changing gate voltage signal.

[0067] According to one embodiment of the present invention, such as Figure 4 As shown, this invention provides a control device 100 for a single-photon sensor, capable of adjusting the superposition signal range of a DC voltage signal and a periodically changing gate voltage signal. This provides excellent control for avalanche photodiodes, improving the detection efficiency and photon counting rate of the single-photon detection device. The control device 100 for the single-photon sensor includes: a first voltage module 110 and a second voltage module 120. Wherein:

[0068] A first voltage module 110 is coupled to the single-photon sensor and configured to apply a first voltage signal to the single-photon sensor, the first voltage signal including a DC voltage signal. Typically, the first voltage signal applied by the first voltage module 110 to the single-photon sensor is close to the breakdown voltage of the single-photon sensor; that is, the first voltage signal is set near the boundary between the linear operating region and the avalanche region of the single-photon sensor, so that the single-photon sensor is in a critical breakdown state.

[0069] The second voltage module 120 is coupled to the single-photon sensor and configured to apply a second voltage signal to the single-photon sensor. The second voltage signal includes a periodically changing voltage signal, and the first voltage signal is superimposed on the second voltage signal to cause the single-photon sensor to operate alternately in the avalanche region and the cutoff region. The periodic change of the second voltage signal can alter the operating region of the single-photon sensor. During half a cycle of the second voltage signal, the reverse bias voltage applied to the single-photon sensor is higher, and the single-photon sensor operates in the avalanche region, where receiving a single-photon level optical signal triggers an avalanche and outputs an avalanche current. During the other half cycle of the second voltage signal, the voltage applied to the single-photon sensor is lower, and the single-photon sensor operates in the cutoff region. Due to the lack of voltage, the avalanche current is rapidly quenched, thus reducing the avalanche charge and the recovery time after an avalanche.

[0070] According to an embodiment of the present invention, in the control device 100 of the single-photon sensor, when the first voltage signal and the second voltage signal are in the same direction, the absolute value of the superimposed signal of the first voltage signal and the second voltage signal is greater than a first threshold. The first threshold is greater than or equal to the breakdown voltage of the single-photon sensor. By controlling the first voltage signal applied by the first voltage module 110 and the second voltage signal applied by the second voltage module 120, when the first voltage signal and the second voltage signal are in the same direction, the superimposed signal of the two is greater than the breakdown voltage of the single-photon sensor, and the single-photon sensor operates in the avalanche region. Within half a cycle when the first voltage signal and the second voltage signal are in the same direction, the single-photon sensor can generate an avalanche upon receiving a single-photon level optical signal and output an avalanche current.

[0071] According to one embodiment of the present invention, since the higher the reverse bias voltage of the single-photon sensor, the more significant the afterpulse effect, in order to suppress the afterpulse, the first voltage signal applied by the first voltage module 110 and the second voltage signal applied by the second voltage module 120 are controlled so that when the first voltage signal and the second voltage signal are in the same direction, the absolute value of the superimposed signal of the first voltage signal and the second voltage signal is less than a fourth threshold. The fourth threshold is determined according to the current-voltage characteristics of the single-photon sensor.

[0072] According to an embodiment of the present invention, in the control device 100 of the single-photon sensor, when the first voltage signal and the second voltage signal are in opposite directions, the absolute value of the superimposed signal of the first voltage signal and the second voltage signal is less than a second threshold. The second threshold is less than or equal to the forward conduction voltage of the single-photon sensor. By controlling the first voltage signal applied by the first voltage module 110 and the second voltage signal applied by the second voltage module 120, when the first voltage signal and the second voltage signal are in opposite directions, the superimposed signal of the two is less than the second threshold. That is, when the superimposed signal of the first voltage signal and the second voltage signal is a forward voltage signal, the superimposed signal should be less than the forward conduction voltage of the single-photon sensor, thus preventing the superimposed signal from causing the single-photon sensor to conduct forward and thus damaging the single-photon sensor.

[0073] According to one embodiment of the present invention, by controlling the first voltage signal applied by the first voltage module 110 and the second voltage signal applied by the second voltage module 120, when the first voltage signal and the second voltage signal are in opposite directions, the superimposed signal of the two is close to zero voltage. Due to the lack of voltage, the avalanche current can be rapidly quenched. During the half-cycle when the first voltage signal and the second voltage signal are in opposite directions, the avalanche charge and the recovery time (dead time) after the avalanche are reduced.

[0074] According to one embodiment of the present invention, such as Figure 5 As shown, in the control device 100 for the single-photon sensor, the second voltage module 120 includes: a signal generation submodule 121 and a signal amplification submodule 122. Wherein:

[0075] The signal generation submodule 121 is configured to generate a periodically changing voltage signal;

[0076] The signal amplification submodule 122 is coupled to the signal generation submodule 121 and configured to amplify the voltage signal generated by the signal generation submodule 121.

[0077] According to one embodiment of the present invention, the signal amplification submodule 122 includes a transformer, optionally implemented by one or more step-up transformers. The transformer amplifies the periodically changing voltage signal generated by the signal generation submodule 121, while keeping the power of the second voltage module 120 and its transmission line constant. That is, only a low-power AC voltage signal is needed to generate a higher gate voltage signal, which is then applied to the single-photon sensor.

[0078] According to one embodiment of the present invention, such as Figure 6 As shown, the control device 100 for the single-photon sensing device further includes a control module 130. Wherein...

[0079] The control module 130 is coupled to the first voltage module 110 and the second voltage module 120 respectively, and is configured to control the output of the second voltage module 120 according to the first voltage signal.

[0080] If the first voltage module 110 does not apply a first voltage signal to the single-photon sensor, and the second voltage module 120 applies a second voltage signal to the single-photon sensor, then within half a cycle of the periodically changing second voltage signal, it is equivalent to applying a forward voltage to the single-photon sensor. When the forward voltage is greater than the forward conduction voltage of the single-photon sensor, the single-photon sensor conducts in the forward direction, which can easily damage the single-photon sensor. Therefore, a control module 130 is provided to control the output of the second voltage module 120 based on whether the first voltage module 110 is outputting the first voltage signal normally.

[0081] According to an embodiment of the present invention, in the control device 100 of the single-photon sensing device, the control module 130 is further configured to:

[0082] When the first voltage signal is less than the third threshold, the second voltage module 120 is controlled to stop applying the second voltage signal to the single-photon sensor.

[0083] If the first voltage signal applied by the first voltage module 110 to the single-photon sensor is less than a third threshold, and the second voltage module 120 applies a second voltage signal to the single-photon sensor, then within half a cycle of the periodically changing second voltage signal, the superimposed signal of the first and second voltage signals may still generate a large positive voltage. When this positive voltage exceeds the forward conduction voltage of the single-photon sensor, the single-photon sensor conducts forward, which can easily damage the single-photon sensor. Therefore, a third threshold is set, and when the first voltage signal is less than the third threshold, the second voltage module 120 is controlled to stop applying the second voltage signal to the single-photon sensor. The third threshold is determined based on the amplitude of the positive period of the second voltage signal.

[0084] According to one embodiment of the present invention, such as Figure 7 As shown, in the control device 100 for the single-photon sensor, the control module 130 includes a dual-channel relay 131. Wherein:

[0085] The dual-channel relay 131 has a control terminal, a first terminal, a second terminal, and a third terminal. The control terminal is coupled to the first voltage module 110, the first terminal is coupled to the signal generation submodule 121, the second terminal is coupled to the signal amplification submodule 122, and the third terminal is coupled to the load. The dual-channel relay 131 is configured as follows:

[0086] Based on the first voltage signal, control the first terminal to be connected to the second terminal, or the first terminal to be connected to the third terminal.

[0087] Optionally, the dual-channel relay 131 includes a single-pole double-throw (SPDT) RF switch. The SPDT RF switch has a safety protection mode; when the switch is de-energized, it defaults to the load side, meaning it defaults to connecting the first terminal and the third terminal, ensuring that the gate voltage signal input from the second voltage module 120 is not applied to the single-photon sensor. When the first voltage signal meets a threshold condition, the SPDT switch controls the first terminal to connect to the second terminal. The periodically changing voltage signal generated by the signal generation module 121 is input to the signal amplification module 122 for amplification and then applied to the single-photon sensor.

[0088] According to one embodiment of the present invention, such as Figure 8 As shown, in the control device 100 for the single-photon sensing device, the control module 130 further includes an AND gate circuit 132. Wherein:

[0089] AND gate 132 has a first input terminal, a second input terminal, and an output terminal. The first input terminal is coupled to the first voltage module 110, the second input terminal is coupled to the DC power supply, and the output terminal is coupled to the control terminal of the dual-channel relay 131. AND gate 132 is configured as follows:

[0090] Based on the first voltage signal, a control signal is output to the control terminal of the dual-channel relay 131.

[0091] The single-photon sensor has a very small DC bias voltage driving current and a large operating range. Therefore, it is necessary to add a gate circuit to adjust and match the DC bias voltage of the single-photon sensor with the control voltage of the control terminal of the single-pole double-throw RF switch.

[0092] When the output voltage of DC voltage is greater than a certain value, the input AND gate circuit 132 judges it as logic "1". When the first voltage signal meets the threshold condition, the voltage division of the input AND gate circuit 132 is greater than a certain value, and it is judged as logic "1". At this time, the AND gate circuit 132 outputs a drive current, which drives the dual-channel relay 131 from the default closed state (the state of connecting the first terminal and the load) to the state of connecting the first terminal and the second terminal, that is, controls the dual-channel relay 131 to connect the signal generation submodule 121 and the signal amplification submodule 122.

[0093] According to one embodiment of the present invention, the single-photon sensing device includes a semiconductor avalanche photodiode. In the control device 100 of the single-photon sensing device, the characteristic impedance of the input terminal of the second voltage module 120 is greater than 200Ω. By adjusting through one or more step-up transformers, the original alternating voltage signal is increased, the characteristic impedance is increased, and the power consumption on the transmission line of the second voltage module 120 remains basically unchanged.

[0094] According to one embodiment of the present invention, such as Figure 9 As shown, in the control device 100 for the single-photon sensor, a GRF6011 single-pole double-throw RF switch is used, a TC4-25G2+ first-stage boost transformer is used, and an MC74VHC1G126DBVT1G AND gate circuit is used to construct a circuit that couples the control device 100 to the single-photon sensor. The control device 100 has ports 1, 2, and 3. Port 1 is used to input a periodically changing voltage signal, and port 2 is used to output a detection signal. Only when a voltage of 30-85V is applied to port 3 (the voltage divider node of the DC bias voltage) will the first terminal of the GRF6011 be connected to the second terminal (the first-stage boost transformer TC4-25G2+). In other cases, the first terminal of the GRF6011 is connected to the third terminal (the load port).

[0095] According to one embodiment of the present invention, such as Figure 10 As shown, the present invention also provides a single-photon detection device 200, including a single-photon sensing device 210 and a control device 100 as described above. Wherein:

[0096] The single-photon sensor 210 is configured to receive optical signals and convert them into electrical signals for output;

[0097] The control device 100, as described above, is coupled to the single-photon sensor 210 and configured to apply a voltage to the single-photon sensor 210.

[0098] According to one embodiment of the present invention, the present invention also provides a chip including a single-photon detection device 200 as described above integrated thereon.

[0099] According to one embodiment of the present invention, such as Figure 11 As shown, the present invention also provides a method 10 for controlling a single-photon sensing device using the control device 100 described above, comprising steps S101-S102. Wherein:

[0100] In step S101, the first voltage signal is applied to the single-photon sensor through the first voltage module;

[0101] In step S102, the second voltage signal is applied to the single-photon sensor through the second voltage module.

[0102] According to an embodiment of the present invention, the method 10 for controlling a single-photon sensing device further includes:

[0103] When the first voltage signal and the second voltage signal are in the same direction, control the first voltage module and / or the second voltage module to make the absolute value of the superimposed signal greater than the first threshold.

[0104] When the first voltage signal is opposite to the second voltage signal, the first voltage module and / or the second voltage module are controlled to make the absolute value of the superimposed signal less than the second threshold.

[0105] According to an embodiment of the present invention, the second voltage module includes: a signal generation submodule and a signal amplification submodule, the signal generation submodule being coupled to the signal amplification submodule, the signal amplification submodule including a transformer, and the method 10 for controlling the single-photon sensing device further includes:

[0106] The signal generation submodule generates a periodically changing voltage signal;

[0107] The voltage signal generated by the signal generation submodule is amplified by the signal amplification submodule.

[0108] According to an embodiment of the present invention, the control device further includes a control module coupled to the first voltage module and the second voltage module respectively, and the method 10 for controlling the single-photon sensing device further includes:

[0109] The control module controls the output of the second voltage module according to the first voltage signal.

[0110] According to an embodiment of the present invention, the method 10 for controlling a single-photon sensing device further includes:

[0111] When the first voltage signal is less than the third threshold, the control module controls the second voltage module to stop applying the second voltage signal to the single-photon sensor.

[0112] According to an embodiment of the present invention, the control module further includes: a dual-channel relay having a control terminal, a first terminal, a second terminal, and a third terminal, wherein the first terminal is coupled to the signal generation submodule, the second terminal is coupled to the signal amplification submodule, and the third terminal is coupled to the load; an AND gate circuit having a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal is coupled to the first voltage module, the second input terminal is coupled to a DC power supply, and the output terminal is coupled to the control terminal of the dual-channel relay; the method 10 for controlling the single-photon sensing device further includes:

[0113] The AND gate circuit outputs a control signal to the control terminal of the dual-channel relay based on the first voltage signal.

[0114] The dual-channel relay controls the first terminal to be connected to the second terminal, or the first terminal to be connected to the third terminal.

[0115] The specific limitations of the method 10 for controlling the single-photon sensor described above are similar to those in the control device 100 for the single-photon sensor. Please refer to the above description of the control device 100 for the single-photon sensor, which will not be repeated here.

[0116] The control device and method for controlling a single-photon sensor provided by one or more embodiments of the present invention apply a DC bias voltage and a gated alternating signal to the single-photon sensor through a DC voltage module and an AC voltage module, causing the single-photon sensor to operate alternately in the avalanche region and the cutoff region. This effectively controls the superposition range of the DC voltage signal and the periodically changing gated voltage signal. The present invention uses one or more step-up transformers to amplify the gated alternating signal, and the characteristic impedance of the transmission line at the gated signal terminal is also increased accordingly, so that the power consumption remains essentially constant. Only a relatively low-power AC voltage signal is needed to generate a higher gated alternating signal, which is then applied to the single-photon sensor. The present invention also implements a bias protection function through a single-pole double-throw RF switch and its use in conjunction with gate circuits, preventing the amplified gated alternating voltage signal from damaging the single-photon sensor.

Claims

1. A control device for a single-photon sensing device, characterized in that, include: A first voltage module is coupled to the single-photon sensor and configured to apply a first voltage signal to the single-photon sensor, the first voltage signal including a DC voltage signal; A second voltage module, coupled to the single-photon sensor, is configured to apply a second voltage signal to the single-photon sensor. The second voltage signal includes a periodically changing voltage signal. The second voltage module includes: The signal generation submodule is configured to generate periodically changing voltage signals; A signal amplification submodule, coupled to the signal generation submodule, is configured to amplify the voltage signal generated by the signal generation submodule, and the signal amplification submodule includes a transformer; The first voltage signal is superimposed on the second voltage signal to cause the single-photon sensor to operate alternately in the avalanche region and the cutoff region, wherein: When the first voltage signal and the second voltage signal are in the same direction, the absolute value of the superimposed signal of the first voltage signal and the second voltage signal is greater than a first threshold, and the first threshold is greater than or equal to the breakdown voltage of the single-photon sensor. When the first voltage signal is opposite to the second voltage signal, the absolute value of the superimposed signal of the first voltage signal and the second voltage signal is less than the second threshold, and the second threshold is less than or equal to the forward conduction voltage of the single-photon sensor.

2. The control device as claimed in claim 1, further comprising: The control module is coupled to the first voltage module and the second voltage module respectively, and is configured to control the output of the second voltage module according to the first voltage signal.

3. The control device as claimed in claim 2, wherein the control module is further configured to: When the first voltage signal is less than the third threshold, the second voltage module is controlled to stop applying the second voltage signal to the single-photon sensor.

4. The control device as described in claim 2 or 3, wherein the control module comprises: A dual-channel relay has a control terminal, a first terminal, a second terminal, and a third terminal. The control terminal is coupled to the first voltage module, the first terminal is coupled to the signal generation submodule, the second terminal is coupled to the signal amplification submodule, and the third terminal is coupled to the load. The dual-channel relay is configured as follows: Based on the first voltage signal, control the first terminal to be connected to the second terminal, or the first terminal to be connected to the third terminal.

5. The control device as claimed in claim 4, wherein the control module further comprises: An AND gate circuit has a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal is coupled to the first voltage module, the second input terminal is coupled to a DC power supply, and the output terminal is coupled to the control terminal of the dual-channel relay. The AND gate circuit is configured as follows: Based on the first voltage signal, a control signal is output to the control terminal of the dual-channel relay.

6. The control device as claimed in claim 4, wherein the single-photon sensing device includes an avalanche photodiode, the transformer includes one or more step-up transformers, and the dual-channel relay includes a single-pole double-throw radio frequency switch.

7. A single-photon detection device, characterized in that, include: A single-photon sensor is configured to receive optical signals and convert them into electrical signals for output. The control device as described in any one of claims 1-6 is coupled to the single-photon sensing device and configured to apply a voltage to the single-photon sensing device.

8. A chip, characterized in that, Including the single-photon detection device as described in claim 7 integrated thereon.

9. A method for controlling a single-photon sensing device using the control device as described in any one of claims 1-6, characterized in that, include: The first voltage signal is applied to the single-photon sensor through the first voltage module; The second voltage signal is applied to the single-photon sensor via the second voltage module.

10. The method of claim 9, further comprising: When the first voltage signal and the second voltage signal are in the same direction, control the first voltage module and / or the second voltage module to make the absolute value of the superimposed signal greater than the first threshold. When the first voltage signal is opposite to the second voltage signal, the first voltage module and / or the second voltage module are controlled to make the absolute value of the superimposed signal less than the second threshold.

11. The method of claim 9 or 10, wherein the second voltage module comprises: The method includes a signal generation submodule and a signal amplification submodule, wherein the signal generation submodule is coupled to the signal amplification submodule, and the signal amplification submodule includes a transformer. The signal generation submodule generates a periodically changing voltage signal; The voltage signal generated by the signal generation submodule is amplified by the signal amplification submodule.

12. The method of claim 11, wherein the control device further comprises a control module, the control module being coupled to the first voltage module and the second voltage module respectively, and the method further comprises: The control module controls the output of the second voltage module according to the first voltage signal.

13. The method of claim 12, further comprising: When the first voltage signal is less than the third threshold, the control module controls the second voltage module to stop applying the second voltage signal to the single-photon sensor.

14. The method of claim 12 or 13, wherein the control module further comprises: A dual-channel relay and an AND gate circuit are provided. The dual-channel relay has a control terminal, a first terminal, a second terminal, and a third terminal. The first terminal is coupled to the signal generation submodule, the second terminal is coupled to the signal amplification submodule, and the third terminal is coupled to the load. The AND gate circuit has a first input terminal, a second input terminal, and an output terminal. The first input terminal is coupled to the first voltage module, the second input terminal is coupled to a DC power supply, and the output terminal is coupled to the control terminal of the dual-channel relay. The method further includes: The AND gate circuit outputs a control signal to the control terminal of the dual-channel relay based on the first voltage signal. The dual-channel relay controls the first terminal to be connected to the second terminal, or the first terminal to be connected to the third terminal.

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