Front-end gate circuit chip and system for sine-gated single-photon detector

Abstract

The invention provides a front-end gate circuit chip and system for a sine gating single-photon detector, which can be applied to the technical field of single-photon detection. The chip comprises: a coincidence gate signal generation module configured to perform band-pass filtering and low noise amplification on a frequency reference signal input to a front-end gate circuit chip to obtain an intermediate coincidence gate signal, perform phase shift on the intermediate coincidence gate signal to obtain a coincidence gate signal, and output the coincidence gate signal; a sine gate signal generation module electrically connected with the gate signal generation module and configured to receive the intermediate coincidence gate signal, amplify the intermediate coincidence gate signal to obtain an intermediate sine gate signal, filter the intermediate sine gate signal to obtain a sine gate signal, and output the sine gate signal; and the sine width detection signal generation module is electrically connected with the sine gate signal generation module, and is configured to receive the intermediate sine gate signal, detect and amplify the intermediate sine gate signal to obtain a sine width detection signal, and output the sine width detection signal.

Description

Technical Field

[0001] The present invention relates to the technical field of single photon detection, and more specifically, to a front-end gate circuit chip and system for a sinusoidally gated single photon detector. Background Art

[0002] High-speed sinusoidally gated single-photon detectors are the core key instruments in practical quantum communication systems. With the large-scale deployment of quantum communication networks, the quantum communication system has increasingly stringent requirements on the size and cost of single-photon detectors, and the design of miniaturized high-speed gated single-photon detectors is urgent. However, due to the complex functions and high power consumption of the front-end gate circuit, there is still no effective integrated solution. Summary of the invention

[0003] In view of this, the present invention provides a front-end gate circuit chip and system for a sinusoidally gated single-photon detector.

[0004] One aspect of the present invention provides a front-end gate circuit chip for a sinusoidal gated single-photon detector, comprising:

[0005] A coincidence gate signal generating module is configured to perform bandpass filtering and low-noise amplification on the frequency reference signal input to the front-end gate circuit chip to obtain an intermediate coincidence gate signal, perform phase shifting on the intermediate coincidence gate signal to obtain a coincidence gate signal, and output the coincidence gate signal, wherein the coincidence gate signal is used for the sinusoidal gated single-photon detector to shield signals outside the effective gate width range;

[0006] a sine gate signal generating module, electrically connected to the gate signal generating module, configured to receive the intermediate coincident gate signal, amplify the intermediate coincident gate signal to obtain an intermediate sinusoidal gate signal, filter the intermediate sinusoidal gate signal to obtain a sinusoidal gate signal, and output the sinusoidal gate signal, wherein the sinusoidal gate signal is used as a gate signal of a single-photon avalanche diode in the sinusoidally gated single-photon detector;

[0007] The sinusoidal gate amplitude detection signal generating module is electrically connected to the above-mentioned sinusoidal gate signal generating module, and is configured to receive the above-mentioned intermediate sinusoidal gate signal, detect and amplify the above-mentioned intermediate sinusoidal gate signal to obtain a sinusoidal gate amplitude detection signal, and output the above-mentioned sinusoidal gate amplitude detection signal, wherein the above-mentioned sinusoidal gate amplitude detection signal is used to detect the amplitude of the above-mentioned sinusoidal gate signal when used in the above-mentioned sinusoidal gated single photon detector.

[0008] According to an embodiment of the present invention, the coincidence gate signal generating module comprises an intermediate coincidence gate signal generating unit, wherein the intermediate coincidence gate signal generating unit comprises a first bandpass filter, a first-stage low noise amplifier, a first attenuator, a first phase shifter, a voltage-controlled attenuator and a second-stage low noise amplifier electrically connected in sequence;

[0009] The first bandpass filter is configured to filter the frequency reference signal to obtain a first intermediate frequency reference signal, and output the first intermediate frequency reference signal;

[0010] The first-stage low noise amplifier and the first attenuator are configured to adjust the amplitude of the first intermediate frequency reference signal to obtain a second intermediate frequency reference signal that meets the amplitude input requirement of the first phase shifter, and output the second intermediate frequency reference signal;

[0011] The first phase shifter is configured to perform initial phase adjustment on the second intermediate frequency reference signal to obtain a third intermediate frequency reference signal, and output the third intermediate frequency reference signal;

[0012] The voltage-controlled attenuator is configured to perform amplitude adjustment on the third intermediate frequency reference signal to obtain a fourth intermediate frequency reference signal, and output the fourth intermediate frequency reference signal;

[0013] The secondary low noise amplifier is configured to amplify the fourth intermediate frequency reference signal to obtain the intermediate coincidence gate signal, and output the intermediate coincidence gate signal.

[0014] According to an embodiment of the present invention, the above-mentioned coincidence gate signal generating module comprises a coincidence gate signal generating unit, and the above-mentioned coincidence gate signal generating unit is electrically connected to the above-mentioned intermediate coincidence gate signal generating unit, wherein the above-mentioned coincidence gate signal generating unit comprises an electrically connected power divider and a second phase shifter;

[0015] The power divider is connected to the secondary low-noise discharge, and the power divider includes two paths, one of which outputs the intermediate coincidence gate signal to the sinusoidal gate signal generating module, and the other outputs the intermediate coincidence gate signal to the second phase shifter;

[0016] The second phase shifter is configured to perform relative phase adjustment on the intermediate coincidence gate signal to obtain the coincidence gate signal, and output the coincidence gate signal.

[0017] According to an embodiment of the present invention, the above-mentioned sinusoidal gate signal generation module includes a second attenuator, a power amplifier, a coupled microstrip line, and a second bandpass filter electrically connected in sequence;

[0018] The second attenuator is configured to attenuate the intermediate coincidence gate signal to obtain a first intermediate coincidence gate signal, and output the first intermediate coincidence gate signal;

[0019] The power amplifier is configured to amplify the first intermediate coincidence gate signal to obtain the intermediate sinusoidal gate signal, and output the intermediate sinusoidal gate signal;

[0020] The coupled microstrip line includes two paths, one of which outputs the intermediate sinusoidal gate signal to the sinusoidal gate amplitude detection signal generating module, and the other outputs the intermediate sinusoidal gate signal to the second bandpass filter;

[0021] The second bandpass filter is configured to filter the intermediate sinusoidal gate signal and then output the sinusoidal gate signal.

[0022] According to an embodiment of the present invention, the above-mentioned sinusoidal gate amplitude detection signal generating module comprises a third attenuator, a detector and an operational amplifier which are electrically connected in sequence;

[0023] The third attenuator is configured to attenuate the intermediate sinusoidal gate signal to obtain a first intermediate sinusoidal gate signal and output the first intermediate sinusoidal gate signal;

[0024] The detector is configured to detect the first intermediate sinusoidal gate signal to obtain a voltage signal and output the voltage signal;

[0025] The operational amplifier is configured to amplify the voltage signal to obtain the sinusoidal gate amplitude detection signal, and output the sinusoidal gate amplitude detection signal.

[0026] According to an embodiment of the present invention, the front-end gate circuit chip further includes:

[0027] A low temperature co-fired ceramic substrate, on which the above-mentioned coincidence gate signal generating module, the above-mentioned sinusoidal gate signal generating module and the above-mentioned sinusoidal gate amplitude detection signal generating module are arranged.

[0028] According to an embodiment of the present invention, the low temperature co-fired ceramic substrate, the coincidence gate signal generating module, the sinusoidal gate signal generating module and the sinusoidal gate amplitude detection signal generating module are packaged in a metal tube shell.

[0029] According to an embodiment of the present invention, the metal tube shell is filled with nitrogen.

[0030] According to an embodiment of the present invention, the length of the front-end gate circuit chip is less than 30 mm, the width is less than 20 mm, and the height is less than 3 mm.

[0031] Another aspect of the present invention provides a sinusoidal-gated single-photon detector system, comprising:

[0032] Sine-gated single-photon detectors; and

[0033] The front-end gate circuit chip as mentioned above is configured to provide a coincidence gate signal, a sinusoidal gate signal and a sinusoidal gate amplitude detection signal to the sinusoidal gated single photon detector.

[0034] According to an embodiment of the present invention, the present invention integrates a coincidence gate signal generation module for generating a coincidence gate signal, a sinusoidal gate signal generation module for generating a sinusoidal gate signal, and a sinusoidal gate amplitude detection signal generation module for generating a sinusoidal gate amplitude detection signal on a chip, which can significantly reduce the volume of the front-end gate circuit of the sinusoidal gated single-photon detector and greatly improve the integration of the high-speed sinusoidal gated single-photon detector. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0036] Figure 1 A block diagram of a front-end gate circuit chip for a sinusoidal-gated single-photon detector according to an embodiment of the present invention is shown;

[0037] Figure 2A A block diagram of a coincidence gate signal generating module of a front-end gate circuit chip for a sinusoidally gated single-photon detector according to an embodiment of the present invention is shown;

[0038] Figure 2B A block diagram showing an intermediate coincidence gate signal generating unit and a coincidence gate signal generating unit of a front-end gate circuit chip for a sinusoidal-gated single-photon detector according to an embodiment of the present invention is shown;

[0039] Figure 3 A block diagram of a sinusoidal gate signal generating module of a front-end gate circuit chip for a sinusoidally gated single-photon detector according to an embodiment of the present invention is shown;

[0040] Figure 4 A block diagram showing a sinusoidal gate amplitude detection signal generating module of a front-end gate circuit chip for a sinusoidal gated single photon detector according to an embodiment of the present invention is shown; and

[0041] Figure 5 A block diagram of a sinusoidally gated single-photon detector system according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0042] Below, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of concepts of the present invention.

[0043] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0044] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0045] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0046] High-speed sinusoidally gated single-photon detectors are the core key instruments in practical quantum communication systems. With the large-scale deployment of quantum communication networks, quantum communication systems have increasingly stringent requirements on the size and cost of single-photon detectors. Therefore, the design of miniaturized high-speed gated single-photon detectors is urgent. The generation and detection of high-power, high-frequency sinusoidal gate signals are the core technologies in high-speed sinusoidally gated single-photon detectors. In related technologies, sinusoidal gate signals are mainly implemented using board-level discrete devices, which occupy a large volume. In addition, the front-end gate circuit has complex functions and high power consumption.

[0047] In view of this, an embodiment of the present invention provides a front-end gate circuit chip for a sinusoidal gated single-photon detector, including a coincidence gate signal generating module, configured to perform bandpass filtering and low-noise amplification on a frequency reference signal input to the front-end gate circuit chip to obtain an intermediate coincidence gate signal, phase-shift the intermediate coincidence gate signal to obtain a coincidence gate signal, and output the coincidence gate signal, wherein the coincidence gate signal is used for the sinusoidal gated single-photon detector to shield signals outside the effective gate width range; a sinusoidal gate signal generating module, electrically connected to the gate signal generating module, configured to receive the intermediate coincidence gate signal, phase-shift the intermediate coincidence gate signal to obtain a coincidence gate signal, and output the coincidence gate signal. The gate signal is amplified to obtain an intermediate sinusoidal gate signal, the intermediate sinusoidal gate signal is filtered to obtain a sinusoidal gate signal, and the sinusoidal gate signal is output, wherein the sinusoidal gate signal is used as the gate signal of the single-photon avalanche diode in the sinusoidally gated single-photon detector; a sinusoidal gate amplitude detection signal generating module is electrically connected to the sinusoidal gate signal generating module, configured to receive the intermediate sinusoidal gate signal, detect and amplify the intermediate sinusoidal gate signal to obtain a sinusoidal gate amplitude detection signal, and output a sinusoidal gate amplitude detection signal, wherein the sinusoidal gate amplitude detection signal is used to detect the amplitude of the sinusoidal gate signal when used in the sinusoidally gated single-photon detector.

[0048] Figure 1 A block diagram of a front-end gate circuit chip for a sinusoidally gated single-photon detector according to an embodiment of the present invention is shown.

[0049] like Figure 1 As shown, the front-end gate circuit chip 100 for the sinusoidal gated single photon detector includes a coincidence gate signal generating module 110 , a sinusoidal gate signal generating module 120 and a sinusoidal gate amplitude detection signal generating module 130 .

[0050] The coincidence gate signal generating module 110 is configured to perform bandpass filtering and low-noise amplification on the frequency reference signal input to the front-end gate circuit chip to obtain an intermediate coincidence gate signal, phase-shift the intermediate coincidence gate signal to obtain a coincidence gate signal, and output the coincidence gate signal, wherein the coincidence gate signal is used for the sinusoidally gated single-photon detector to shield signals outside the effective gate width range.

[0051] The sinusoidal gate signal generating module 120 is electrically connected to the gate signal generating module 110, and is configured to receive an intermediate coincident gate signal, amplify the intermediate coincident gate signal to obtain an intermediate sinusoidal gate signal, filter the intermediate sinusoidal gate signal to obtain a sinusoidal gate signal, and output a sinusoidal gate signal, wherein the sinusoidal gate signal is used as a gate signal of a single-photon avalanche diode in a sinusoidally gated single-photon detector.

[0052] The sinusoidal gate amplitude detection signal generating module 130 is electrically connected to the sinusoidal gate signal generating module 120, and is configured to receive an intermediate sinusoidal gate signal, detect and amplify the intermediate sinusoidal gate signal to obtain a sinusoidal gate amplitude detection signal, and output a sinusoidal gate amplitude detection signal, wherein the sinusoidal gate amplitude detection signal is used to detect the amplitude of the sinusoidal gate signal when used in a sinusoidally gated single photon detector.

[0053] According to an embodiment of the present invention, the coincidence gate signal generation module is configured to generate a coincidence gate signal using a frequency reference signal and provide it to a sinusoidal gated single photon detector. The sinusoidal gated single photon detector uses the coincidence gate signal to shield signals outside the effective gate width range and reduce the noise of the sinusoidal gated single photon detector.

[0054] According to an embodiment of the present invention, the coincidence gate signal generation module can also obtain an intermediate coincidence gate signal and provide it to the sinusoidal gate signal generation module. The sinusoidal gate signal generation module is configured to generate a sinusoidal gate signal using the intermediate coincidence gate signal and provide it to the sinusoidally gated single-photon detector. The sinusoidally gated single-photon detector uses the sinusoidal gate signal as the gate signal of the single-photon avalanche diode in the sinusoidally gated single-photon detector.

[0055] According to an embodiment of the present invention, the sinusoidal gate signal generation module can also obtain an intermediate sinusoidal gate signal and provide it to the sinusoidal gate amplitude detection signal generation module. The sinusoidal gate amplitude detection signal generation module is configured to use the intermediate sinusoidal gate signal to generate a sinusoidal gate amplitude detection signal and provide it to the sinusoidal gated single photon detector. The sinusoidal gated single photon detector uses the sinusoidal gate amplitude detection signal to detect the amplitude of the sinusoidal gate signal when it is used in the sinusoidal gated single photon detector, and adjusts the gate amplitude in real time according to the detection situation to ensure stable operation of the detector.

[0056] According to an embodiment of the present invention, the present invention integrates a coincidence gate signal generation module for generating a coincidence gate signal, a sinusoidal gate signal generation module for generating a sinusoidal gate signal, and a sinusoidal gate amplitude detection signal generation module for generating a sinusoidal gate amplitude detection signal on a chip, which can significantly reduce the volume of the front-end gate circuit of the sinusoidal gated single-photon detector and greatly improve the integration of the high-speed sinusoidal gated single-photon detector.

[0057] Figure 2A A block diagram of a coincidence gate signal generation module of a front-end gate circuit chip for a sinusoidally gated single-photon detector according to an embodiment of the present invention is shown.

[0058] Figure 2B A block diagram of an intermediate coincidence gate signal generating unit and a coincidence gate signal generating unit of a front-end gate circuit chip for a sinusoidally gated single-photon detector according to an embodiment of the present invention is shown.

[0059] like Figure 2A and Figure 2BAs shown, the coincidence gate signal generating module 210 includes an intermediate coincidence gate signal generating unit 211 and a coincidence gate signal generating unit 212, wherein the intermediate coincidence gate signal generating unit 211 includes a first bandpass filter 2111, a first low noise amplifier 2112, a first attenuator 2113, a first phase shifter 2114, a voltage-controlled attenuator 2115 and a second low noise amplifier 2116 which are electrically connected in sequence.

[0060] The first bandpass filter 2111 is configured to filter the frequency reference signal to obtain a first intermediate frequency reference signal, and output the first intermediate frequency reference signal.

[0061] The first-stage low noise amplifier 2112 and the first attenuator 2113 are configured to perform amplitude adjustment on the first intermediate frequency reference signal to obtain a second intermediate frequency reference signal that meets the amplitude input requirement of the first phase shifter, and output the second intermediate frequency reference signal.

[0062] The first phase shifter 2114 is configured to perform initial phase adjustment on the second intermediate frequency reference signal to obtain a third intermediate frequency reference signal, and output the third intermediate frequency reference signal.

[0063] The voltage-controlled attenuator 2115 is configured to perform amplitude adjustment on the third intermediate frequency reference signal to obtain a fourth intermediate frequency reference signal, and output the fourth intermediate frequency reference signal.

[0064] The secondary low noise amplifier 2116 is configured to amplify the fourth intermediate frequency reference signal to obtain an intermediate coincidence gate signal, and output the intermediate coincidence gate signal.

[0065] According to an embodiment of the present invention, the coincidence gate signal generating unit 212 is electrically connected to the intermediate coincidence gate signal generating unit 211 , wherein the coincidence gate signal generating unit 212 includes a power divider 2121 and a second phase shifter 2122 that are electrically connected.

[0066] The power divider 2121 is electrically connected to the secondary low noise amplifier 2116 . The power divider 2121 includes two paths, one of which outputs the intermediate coincidence gate signal to the sinusoidal gate signal generating module, and the other outputs the intermediate coincidence gate signal to the second phase shifter 2122 .

[0067] The second phase shifter 2122 is configured to perform relative phase adjustment on the intermediate coincidence gate signal to obtain a coincidence gate signal, and output the coincidence gate signal.

[0068] According to an embodiment of the present invention, the frequency reference signal may be a sinusoidal frequency reference signal with a frequency of 1.25 GHz.

[0069] The frequency reference signal is input to the first bandpass filter in the coincidence gate signal generation module for filtering to obtain a first intermediate frequency reference signal. The first intermediate frequency reference signal is amplitude modulated by sequentially connecting a first low noise amplifier and a first attenuator to meet the input amplitude requirement of the first phase shifter. The first phase shifter can adopt a 6-way digitally controlled phase shifter, and the sine gated single photon detector can adjust the overall phase of the second intermediate frequency reference signal by digitally controlling the first phase shifter, so that the overall phase of the coincidence gate signal and the sine gate signal output by the front-end gate chip is adjusted. The output of the first phase shifter is connected to a voltage-controlled attenuator, and the sine gated single photon detector can adjust the amplitude of the third intermediate frequency reference signal by controlling the voltage-controlled attenuator. The output of the voltage-controlled attenuator is sequentially connected to a second low noise amplifier and a power divider. The second low noise amplifier amplifies the fourth intermediate frequency reference signal to obtain an intermediate coincidence gate signal. The power divider can output two intermediate coincidence gate signals of the same amplitude, one of which outputs an out1 signal, i.e., an intermediate coincidence gate signal, which is output to the sine gate signal generation module. The other output is connected to the second phase shifter, and the second phase shifter can also use a 6-digital controlled phase shifter. The sinusoidal gated single photon detector can adjust the relative phase of the intermediate coincidence gate signal through the digitally controlled second phase shifter, so that the relative phase of the coincidence gate signal and the sinusoidal gate signal output by the front-end gate chip is adjusted. The second phase shifter outputs the out2 signal, which is the coincidence gate signal.

[0070] Figure 3 A block diagram of a sinusoidal gate signal generating module of a front-end gate circuit chip for a sinusoidally gated single-photon detector according to an embodiment of the present invention is shown.

[0071] like Figure 3 As shown, the sinusoidal gate signal generating module 320 includes a second attenuator 321, a power amplifier 322, a coupled microstrip line 323 and a second bandpass filter 324 which are electrically connected in sequence.

[0072] The second attenuator is configured to attenuate the intermediate coincidence gate signal to obtain a first intermediate coincidence gate signal, and output the first intermediate coincidence gate signal.

[0073] The power amplifier is configured to amplify the first intermediate coincidence gate signal to obtain an intermediate sinusoidal gate signal, and output the intermediate sinusoidal gate signal.

[0074] The coupled microstrip line includes two paths, one of which outputs the intermediate sinusoidal gate signal to the sinusoidal gate amplitude detection signal generating module, and the other outputs the intermediate sinusoidal gate signal to the second bandpass filter.

[0075] The second bandpass filter is configured to filter the intermediate sinusoidal gate signal and then output a sinusoidal gate signal.

[0076] According to an embodiment of the present invention, the second attenuator attenuates the intermediate coincident gate signal to obtain the first intermediate coincident gate signal, so that the amplitude of the first intermediate coincident gate signal is controlled within the input range of the power amplifier. The power amplifier amplifies the first intermediate coincident gate signal, for example, by 20 dB. An intermediate sinusoidal gate signal is obtained. The coupled microstrip line can divide the intermediate sinusoidal gate signal into two outputs with a power ratio of 1:99, one of which has an output power ratio of 1%, outputs the out3 signal, i.e., the intermediate sinusoidal gate signal, and outputs it to the sinusoidal gate amplitude detection signal generation module, and the other outputs a power ratio of 99%, and outputs the out4 signal, i.e., the sinusoidal gate signal, after being filtered by the second bandpass filter.

[0077] Figure 4 A block diagram of a sinusoidal gate amplitude detection signal generating module of a front-end gate circuit chip for a sinusoidal gated single photon detector according to an embodiment of the present invention is shown.

[0078] like Figure 4 As shown, the sinusoidal gate amplitude detection signal generating module 430 includes a third attenuator 431, a detector 432 and an operational amplifier 433 which are electrically connected in sequence.

[0079] The third attenuator 431 is configured to attenuate the intermediate sinusoidal gate signal to obtain a first intermediate sinusoidal gate signal and output the first intermediate sinusoidal gate signal.

[0080] The detector 432 is configured to detect the first intermediate sinusoidal gate signal to obtain a voltage signal, and output the voltage signal.

[0081] The operational amplifier 433 is configured to amplify the voltage signal to obtain a sinusoidal gate amplitude detection signal, and output the sinusoidal gate amplitude detection signal.

[0082] According to an embodiment of the present invention, the third attenuator attenuates the intermediate sinusoidal gate signal to obtain a first intermediate sinusoidal gate signal, and outputs the first intermediate sinusoidal gate signal to the detector. The detector obtains a voltage signal according to the power of the first intermediate sinusoidal gate signal, and outputs the voltage signal to the operational amplifier. The operational amplifier amplifies the voltage signal to obtain a sinusoidal gate amplitude detection signal, and outputs the out5 signal, which is the sinusoidal gate amplitude detection signal.

[0083] According to an embodiment of the present invention, since the performance indicators of the sinusoidal gated single-photon detector are very sensitive to the amplitude of the sinusoidal gate signal, in actual use, the amplitude of the sinusoidal gate signal will change slowly with environmental parameters such as temperature and air pressure. The amplitude of the sinusoidal gate signal can be adjusted in real time according to the value of the sinusoidal gate amplitude detection signal, thereby ensuring the stable operation of the sinusoidal gated single-photon detector.

[0084] According to an embodiment of the present invention, the front-end gate circuit chip further includes: a low-temperature co-fired ceramic substrate, on which a gate signal generation module, a sinusoidal gate signal generation module and a sinusoidal gate amplitude detection signal generation module are arranged. The chip die can be welded on the low-temperature co-fired ceramic substrate.

[0085] According to an embodiment of the present invention, the low temperature co-fired ceramic substrate, the coincidence gate signal generation module, the sinusoidal gate signal generation module and the sinusoidal gate amplitude detection signal generation module are packaged in a metal tube shell. The metal tube shell is filled with nitrogen. The metal tube shell can be covered with a Kovar alloy to form a system-level package chip.

[0086] According to an embodiment of the present invention, the length of the front-end gate circuit chip is less than 30 mm, the width is less than 20 mm, and the height is less than 3 mm.

[0087] Figure 5 A block diagram of a sinusoidally gated single-photon detector system according to an embodiment of the present invention is shown.

[0088] like Figure 5 As shown, the sinusoidal gated single photon detector system 500 includes a sinusoidal gated single photon detector 510 and a front-end gate circuit chip 520. The front-end gate circuit chip 520 is configured to provide the sinusoidal gated single photon detector 510 with a coincidence gate signal, a sinusoidal gate signal and a sinusoidal gate amplitude detection signal.

[0089] According to the embodiment of the present invention, the front-end gate circuit chip can refer to the description of other embodiments of the present invention, which will not be repeated here.

[0090] The sinusoidal gated single-photon detector system can achieve wide-range adjustment of the peak-to-peak value of the sinusoidal gate signal and high-precision adjustment of the gate signal delay. At the same time, the dark count noise of the sinusoidal gated single-photon detector when the gate is closed can be filtered out by using the conforming gate signal, and the amplitude of the sinusoidal gate signal can be adjusted in real time through the output value of the sinusoidal gate amplitude detection signal to improve the performance stability of the system. In summary, the front-end gate circuit provided by the present invention realizes the complete functions of the gate circuit, and greatly reduces the circuit volume, which can significantly improve the integration of the system.

[0091] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions. It can be understood by those skilled in the art that the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways, even if such a combination or combination is not explicitly recorded in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways. All these combinations and / or combinations fall within the scope of the present invention.

[0092] The embodiments of the present invention are described above. However, these embodiments are only for the purpose of illustration, and are not intended to limit the scope of the present invention. Although each embodiment is described above, it does not mean that the measures in each embodiment cannot be used in combination advantageously. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A front-end gate circuit chip for a sinusoidal gated single-photon detector, characterized in that: include: A coincidence gate signal generating module is configured to perform bandpass filtering and low-noise amplification on the frequency reference signal input to the front-end gate circuit chip to obtain an intermediate coincidence gate signal, perform phase shifting on the intermediate coincidence gate signal to obtain a coincidence gate signal, and output the coincidence gate signal, wherein the coincidence gate signal is used for the sinusoidal gated single-photon detector to shield signals outside the effective gate width range; a sinusoidal gate signal generating module, electrically connected to the gate signal generating module, configured to receive the intermediate coincident gate signal, amplify the intermediate coincident gate signal to obtain an intermediate sinusoidal gate signal, filter the intermediate sinusoidal gate signal to obtain a sinusoidal gate signal, and output the sinusoidal gate signal, wherein the sinusoidal gate signal is used as a gate signal of a single-photon avalanche diode in the sinusoidally gated single-photon detector; A sinusoidal gate amplitude detection signal generating module is electrically connected to the sinusoidal gate signal generating module, and is configured to receive the intermediate sinusoidal gate signal, detect and amplify the intermediate sinusoidal gate signal to obtain a sinusoidal gate amplitude detection signal, and output the sinusoidal gate amplitude detection signal, wherein the sinusoidal gate amplitude detection signal is used to detect the amplitude of the sinusoidal gate signal when used in the sinusoidal gated single photon detector.

2. The front-end gate circuit chip according to claim 1, characterized in that: The coincidence gate signal generating module comprises an intermediate coincidence gate signal generating unit, wherein the intermediate coincidence gate signal generating unit comprises a first bandpass filter, a first-stage low noise amplifier, a first attenuator, a first phase shifter, a voltage-controlled attenuator and a second-stage low noise amplifier which are electrically connected in sequence; The first bandpass filter is configured to filter the frequency reference signal to obtain a first intermediate frequency reference signal, and output the first intermediate frequency reference signal; The first-stage low noise amplifier and the first attenuator are configured to perform amplitude adjustment on the first intermediate frequency reference signal to obtain a second intermediate frequency reference signal that meets the amplitude input requirement of the first phase shifter, and output the second intermediate frequency reference signal; The first phase shifter is configured to perform initial phase adjustment on the second intermediate frequency reference signal to obtain a third intermediate frequency reference signal, and output the third intermediate frequency reference signal; The voltage-controlled attenuator is configured to perform amplitude adjustment on the third intermediate frequency reference signal to obtain a fourth intermediate frequency reference signal, and output the fourth intermediate frequency reference signal; The secondary low noise amplifier is configured to amplify the fourth intermediate frequency reference signal to obtain the intermediate coincidence gate signal, and output the intermediate coincidence gate signal.

3. The front-end gate circuit chip according to claim 2, characterized in that: The coincidence gate signal generating module comprises a coincidence gate signal generating unit, the coincidence gate signal generating unit is electrically connected to the intermediate coincidence gate signal generating unit, wherein the coincidence gate signal generating unit comprises an electrically connected power divider and a second phase shifter; The power divider is connected to the secondary low-noise discharge, and the power divider includes two paths, one of which outputs the intermediate coincidence gate signal to the sinusoidal gate signal generating module, and the other outputs the intermediate coincidence gate signal to the second phase shifter; The second phase shifter is configured to perform relative phase adjustment on the intermediate coincidence gate signal to obtain the coincidence gate signal, and output the coincidence gate signal.

4. The front-end gate circuit chip according to claim 1, characterized in that: The sinusoidal gate signal generating module comprises a second attenuator, a power amplifier, a coupled microstrip line and a second bandpass filter which are electrically connected in sequence; The second attenuator is configured to attenuate the intermediate coincidence gate signal to obtain a first intermediate coincidence gate signal, and output the first intermediate coincidence gate signal; The power amplifier is configured to amplify the first intermediate coincident gate signal to obtain the intermediate sinusoidal gate signal, and output the intermediate sinusoidal gate signal; The coupled microstrip line includes two paths, one of which outputs the intermediate sinusoidal gate signal to the sinusoidal gate amplitude detection signal generating module, and the other outputs the intermediate sinusoidal gate signal to the second bandpass filter; The second bandpass filter is configured to filter the intermediate sinusoidal gate signal and then output the sinusoidal gate signal.

5. The front-end gate circuit chip according to claim 1, characterized in that: The sinusoidal gate amplitude detection signal generating module comprises a third attenuator, a detector and an operational amplifier which are electrically connected in sequence; The third attenuator is configured to attenuate the intermediate sinusoidal gate signal to obtain a first intermediate sinusoidal gate signal and output the first intermediate sinusoidal gate signal; The detector is configured to detect the first intermediate sinusoidal gate signal to obtain a voltage signal, and output the voltage signal; The operational amplifier is configured to amplify the voltage signal to obtain the sinusoidal gate amplitude detection signal, and output the sinusoidal gate amplitude detection signal.

6. The front-end gate circuit chip according to any one of claims 1 to 5, characterized in that: The front-end gate circuit chip also includes: A low temperature co-fired ceramic substrate, on which the coincidence gate signal generating module, the sinusoidal gate signal generating module and the sinusoidal gate amplitude detection signal generating module are arranged.

7. The front-end gate circuit chip according to claim 6, wherein the low-temperature co-fired ceramic substrate, the coincidence gate signal generating module, the sinusoidal gate signal generating module and the sinusoidal gate amplitude detection signal generating module of the front-end gate circuit chip are packaged in a metal tube shell.

8. The front-end gate circuit chip according to claim 7, characterized in that: The metal tube shell is filled with nitrogen.

9. The front-end gate circuit chip according to any one of claims 1 to 5, characterized in that: The front-end gate circuit chip has a length of less than 30 mm, a width of less than 20 mm, and a height of less than 3 mm.

10. A sinusoidally gated single photon detector system, characterized in that: include: Sine-gated single-photon detector; as well as The front-end gate circuit chip according to any one of claims 1 to 9, configured to provide a coincidence gate signal, a sinusoidal gate signal and a sinusoidal gate amplitude detection signal to the sinusoidal gated single photon detector.

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