WO2022163577A1 - 光子検出装置、受信装置、量子鍵配送システム及び量子信号の検出方法 - Google Patents
光子検出装置、受信装置、量子鍵配送システム及び量子信号の検出方法 Download PDFInfo
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- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
- H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
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- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
- H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
- H04L9/0852—Quantum cryptography
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J1/00—Photometry, e.g. photographic exposure meter
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- G—PHYSICS
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- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J11/00—Measuring the characteristics of individual optical pulses or of optical pulse trains
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- H01L31/08—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors
- H01L31/10—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors characterised by potential barriers, e.g. phototransistors
- H01L31/101—Devices sensitive to infrared, visible or ultraviolet radiation
- H01L31/102—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier
- H01L31/107—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier the potential barrier working in avalanche mode, e.g. avalanche photodiodes
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/60—Receivers
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- H—ELECTRICITY
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- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/70—Photonic quantum communication
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- H—ELECTRICITY
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- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/002—Countermeasures against attacks on cryptographic mechanisms
- H04L9/005—Countermeasures against attacks on cryptographic mechanisms for timing attacks
Definitions
- the present invention relates to a photon detection device, a receiving device, a quantum key distribution system, and a quantum signal detection method.
- Patent Documents 1 to 5 As the Internet spreads, the social needs for encryption technology, such as confidentiality of communications, prevention of falsification, and personal authentication, are increasing. Against this background, in order to ensure the security of communications, the use of quantum key distribution technology, which in principle makes eavesdropping difficult, is attracting attention.
- a quantum signal is generally sent from a transmitting device to a receiving device, and the quantum signals are detected using multiple photon detectors provided in the receiving device.
- the detection efficiency of the photon detector if there is a variation (bias) in the detection efficiency of the photon detector, there is a possibility that it will be used for eavesdropping. Eavesdropping using such biased information is widely known in cryptography. Therefore, it is known that the detection efficiency of the photon detector should be uniform in order to effectively prevent eavesdropping.
- Non-Patent Document 1 a wiretapping technique called a time shift attack
- multiple photon detectors are used to detect quantum signals.
- one photon carries a quantum signal, but in reality there may be two or more photons.
- the intensity of the quantum signal is weak, so the photon detector uses an avalanche photodiode (APD) that can amplify and output the weak signal it receives.
- APD avalanche photodiode
- An APD can amplify a signal by triggering an electron avalanche phenomenon triggered by electrons generated when a photon is incident while a reverse bias exceeding the breakdown voltage is applied. Therefore, in quantum key distribution, the reverse bias voltage applied to the APD is increased so as to synchronize with the incident timing of the photons of the quantum signal (eg, Patent Document 1).
- FIG. 10 schematically shows the timing of voltage application to the APD and the time dependence of the photon detection efficiency. The photon detection efficiency of the APD is maximized when the timing of applying the reverse bias to the APD coincides with the timing of the incident photons.
- FIG. 11 shows an example of dependence of photon detection efficiency of a plurality of photon detectors on incident timing.
- FIG. 11 shows an example in which 0 and 1 bits of the X basis and 0 and 1 bits of the Z basis are detected by four photon detectors. As shown in FIG. 11, even if photons enter at the same timing (for example, timing T in FIG. 11), the photon detection efficiency varies among the plurality of photon detectors.
- Each of the plurality of photon detectors is assigned to each bit of one of the bases of the quantum signal.
- the detection efficiency is analyzed and can result in situations that allow eavesdropping. Therefore, it is required to prevent or suppress the influence of the incident timing dependency of the photon detection efficiency of the photon detector.
- the present invention has been made in view of the above circumstances, and aims to prevent eavesdropping in quantum key distribution.
- a photon detection device includes: a photon detector that outputs a current signal indicating a detection result of a quantum signal; a current-voltage converter that converts the current signal into a voltage signal; An analog-digital converter that outputs a digitally converted output signal, and a signal processing unit that performs predetermined signal processing on the output signal and outputs a detection signal indicating the detection result of the quantum signal, wherein the photon
- the detection signal is not output from the signal processing unit. It is.
- a receiving device includes a photon detection device that detects a quantum signal, the photon detection device including a photon detector that outputs a current signal indicating a detection result of the quantum signal, and a photon detector that outputs the current signal.
- a current-voltage conversion unit that converts the voltage signal into a voltage signal; an analog-digital converter that outputs an output signal obtained by analog-digital conversion of the voltage signal; and a detection result of the quantum signal by performing predetermined signal processing on the output signal.
- a signal processing unit that outputs a detection signal indicating that the time difference between the timing at which the current signal is output from the photon detector and the reference timing determined based on the clock signal falls within the determination range If it does not fit, the detection signal is not output from the signal processing section.
- a quantum key distribution system includes a transmitting device that transmits a quantum signal, and a receiving device that includes a photon detection device that detects the quantum signal, and the photon detection device detects the quantum signal.
- a photon detector that outputs a current signal indicating a detection result
- a current-voltage converter that converts the current signal into a voltage signal
- an analog-digital converter that outputs an output signal obtained by analog-digital conversion of the voltage signal
- a signal processing unit that performs predetermined signal processing on the output signal and outputs a detection signal indicating a detection result of the quantum signal, the timing of outputting the current signal from the photon detector and a clock signal
- the detection signal is not output from the signal processing unit when the time difference between the reference timing determined based on the above and the reference timing does not fall within the determination range.
- a quantum signal detection method outputs a current signal indicating a detection result of a quantum signal, converts the current signal to a voltage signal, and outputs an output signal obtained by analog-digital conversion of the voltage signal. performing predetermined signal processing on the output signal, outputting a detection signal indicating the detection result of the quantum signal, outputting the current signal, a reference timing determined based on a clock signal, If the time difference between is not within the judgment range, the detection signal is not output.
- wiretapping in quantum key distribution can be prevented.
- FIG. 1 is a diagram showing a schematic configuration of a quantum key distribution system
- FIG. 1 is a diagram schematically showing a basic configuration of a receiving device according to Embodiment 1
- FIG. 1 is a diagram schematically showing a configuration example of a receiving device according to Embodiment 1
- FIG. 1 is a diagram schematically showing the configuration of a photon detection device according to Embodiment 1
- FIG. 1 is a diagram schematically showing the configuration of a synchronization signal receiving apparatus according to Embodiment 1
- FIG. 5 is a diagram showing the flow of signals in wiretapping prevention operation in the photon detection device according to the first embodiment
- FIG. 4 is a flowchart of wiretapping prevention operation in the photon detection device according to the first embodiment
- 5 is a diagram showing the flow of signals in wiretapping prevention operation in the photon detection device according to the first embodiment
- FIG. 4 is a flowchart of wiretapping prevention operation in the photon detection device according to the first embodiment
- FIG. 4 is a diagram schematically showing the timing of voltage application to the APD and the time dependence of photon detection efficiency
- FIG. 4 is a diagram showing an example of dependence of photon detection efficiency of a plurality of photon detectors on incident timing.
- Embodiment 1 A quantum key distribution system 1000 according to the first embodiment will be described.
- the quantum key distribution system 1000 is configured, for example, to which the BB84 protocol of phase encoding or polarization encoding is applied.
- Fig. 1 shows a schematic configuration of the quantum key distribution system 1000.
- Quantum key distribution system 1000 has transmitting device 110 , receiving device 100 , and transmission paths 120 and 130 .
- Transmitting device 110 outputs to receiving device 100, via transmission path 120, quantum signal Q used for assigning an encryption key to receiving device 100 and synchronization signal S used for controlling the detection timing of quantum signal Q. do.
- the transmitting device 110 and the receiving device 100 can transmit and receive signals including, for example, base information, test bits, error correction information, etc., via the transmission path 130, which is a public communication path.
- Quantum signal Q is an optical signal transmitted as an optical pulse consisting of a single photon or a number of photons sufficient to produce a quantum effect.
- the synchronization signal S is an optical signal transmitted through the transmission line 120 used for transmission of the quantum signal Q.
- the quantum signal Q and the synchronization signal S are, for example, optical signals with different wavelengths, and may be wavelength-multiplexed and transmitted to the receiver 100 .
- FIG. 2 schematically shows the basic configuration of the receiving device 100 according to the first embodiment.
- the receiver 100 has a photon detector 10 , a synchronization signal receiver 20 and a clock signal generator 30 .
- a quantum signal Q and a synchronization signal S are input to the receiving device 100 , the quantum signal Q is detected by the photon detection device 10 , and the synchronization signal S is received by the synchronization signal receiving device 20 .
- the clock signal generation unit 30 is configured, for example, as a phase locked loop (PLL), generates a clock signal CLK, and outputs it to the photon detection device 10 and the synchronization signal reception device 20 .
- the clock signal generation unit 30 adjusts the timing of the clock signal CLK according to the reference signal REF that notifies the reception timing of the synchronization signal S and is given from the synchronization signal receiving device 20 .
- the clock signal CLK is generated as a high-speed clock signal having higher time accuracy than the reverse bias pulse timing signal and the output voltage signal, which will be described later.
- FIG. 3 schematically shows a configuration example of the receiving apparatus 100 according to the first embodiment.
- the receiver 100 is provided with, for example, a wavelength separation unit 40 that separates the quantum signal Q and the synchronization signal S by wavelength.
- the quantum signal Q can be detected by the photon detector 10 and the synchronization signal S can be received by the synchronization signal receiver 20 .
- the wavelength separating section 40 can be configured as arbitrary wavelength separating means such as a WDM coupler, for example.
- the photon detection device 10 will be explained.
- the photon detection device is provided with a plurality of circuit configurations shown in FIG. 4 below according to the basis used in quantum key distribution.
- a configuration for distributing photons to multiple photon detectors (avalanche photodiodes) according to the encoding scheme (phase encoding, polarization encoding, etc.) applied to the quantum signal to be transmitted (not required for simplification). shown) is also provided.
- FIG. 4 schematically shows the configuration of the photon detection device 10 according to the first embodiment.
- the photon detection device 10 according to the first embodiment has a timing generator 11 , a power supply 12 , an avalanche photodiode (APD) 13 , a current-voltage converter 14 , a sampling unit 15 and a signal processor 16 .
- APD avalanche photodiode
- the timing generation section 11 generates a reverse bias pulse timing signal S11 according to the clock signal CLK and outputs it to the power supply section 12 .
- the clock signal CLK is supplied from the synchronizing signal receiving device 20 as will be described later.
- the power supply unit 12 generates a reverse bias voltage VB1 and applies it to the APD 13 according to the reverse bias pulse timing signal S11.
- the reverse bias voltage VB1 includes a DC component below the breakdown voltage of the APD 13 and a reverse bias pulse component above the breakdown voltage.
- the APD 13 when a photon, that is, a quantum signal Q is incident on the light receiving surface at the timing when the reverse bias pulse component is applied to the APD 13, the electron is multiplied by the avalanche (electron avalanche) effect of the generated photoelectron. As a result, the APD 13 outputs the output current I1. Note that dark noise exists even when no photons are incident, and the output current I1 is detected as a current of a constant value.
- the current-voltage conversion section 14 converts the output current I1 (also referred to as a current signal) into an output voltage signal S12 that is a voltage signal, and outputs the output voltage signal S12 to the sampling section 15 .
- a transimpedance amplifier TIA hereinafter or the like is used as the current-voltage converter 14 .
- the sampling unit 15 samples the output voltage signal S12 according to the clock signal CLK, and outputs the output voltage signal S13 having discrete values, that is, a digital signal, to the signal processing unit 16.
- the sampling unit 15 may output a binary digital signal, or may output a multi-value digital signal generated by analog-digital (AD) conversion.
- AD analog-digital
- ADC analog-digital converter
- the signal processing unit 16 performs predetermined signal processing on the output voltage signal S13, which is a digital signal, according to the clock signal CLK, and outputs a photon detection signal OUT indicating the photon reception result.
- FIG. 5 schematically shows the configuration of the synchronization signal receiver 20 according to the first embodiment.
- the synchronization signal receiver 20 has a power supply section 21 , a photodiode 22 , a current-voltage conversion section 23 and a reference signal generation section 24 .
- the power supply unit 21 generates a reverse bias voltage VB2 and applies it to the photodiode 22 .
- the reverse bias voltage VB2 is output as a DC voltage of several volts, for example.
- the photodiode 22 outputs an output current I2 corresponding to the intensity of the incident light when a synchronizing signal S (in this example, a synchronizing signal Sd described later) is incident on the light-receiving surface while a reverse bias voltage VB2 is being applied.
- a synchronizing signal S in this example, a synchronizing signal Sd described later
- the synchronizing signal S has a higher optical intensity than the quantum signal Q, so the type of the photodiode 22 that receives the synchronizing signal S is not particularly limited, and various photodiodes including APDs can be used.
- the current-voltage converter 23 converts the output current I2 into an output voltage signal S21, which is a voltage signal, and outputs the output voltage signal S21 to the reference signal generator .
- a transimpedance amplifier TIA hereinafter or the like is used as the current-voltage converter 23 .
- the reference signal generator 24 outputs the reference signal REF, which is a digital signal, to the clock signal generator 30 according to the output voltage signal S21.
- the reference signal generator 24 may output a binary digital signal, or may output a multi-valued digital signal generated by analog-digital (A/D) conversion.
- the reference signal generator 24 may be configured as, for example, a clock data recovery (CDR) circuit.
- FIG. 6 shows the signal flow in the wiretapping prevention operation in the photon detection device 10 according to the first embodiment.
- FIG. 7 is a flow chart of wiretapping prevention operation in the photon detection device 10 according to the first embodiment.
- the clock signal CLK is generated according to the received synchronization signal S, so it can be considered an accurate timing signal.
- a false quantum signal QF transmitted by the eavesdropper may enter the receiver 100 .
- the time difference ⁇ t (also referred to as a first time difference) between the timing of the incidence of the clock signal CLK and the quantum signal, that is, the timing at which the output current I1 is output from the APD 13 is detected. , discard the information related to the received quantum signal. This makes it possible to prevent eavesdropping.
- ⁇ t also referred to as a first time difference
- the sampling unit 15 samples the output voltage signal S12, which is an analog signal, according to the clock signal CLK, and converts it into the output voltage signal S13, which is a digital signal.
- the time when the quantum signal Q is incident on the APD 13 (the time when the output current I1 is output) is t
- the time from the time t until the output voltage signal S12 reaches the sampling unit 15 is ⁇ t d1
- the clock signal CLK is The reference timing based on is defined as T ref .
- the sampling unit 15 monitors the time difference ⁇ t between the time t+ ⁇ t d1 at which the output voltage signal S12 reaches the sampling unit 15 and the reference timing Tref, and the time difference ⁇ t is within a predetermined range (first determination (also called range). It can be understood that the sampling unit 15 indirectly monitors the timing at which the output current I1 is output from the APD 13 by monitoring the time difference ⁇ t.
- the sampling unit 15 monitors the time difference ⁇ t, for example, and determines whether the time difference ⁇ t is greater than or equal to a first threshold TH1 (also referred to as a lower threshold) and less than or equal to a second threshold TH2 (also referred to as an upper threshold). (step ST1 in FIG. 7).
- a first threshold TH1 also referred to as a lower threshold
- a second threshold TH2 also referred to as an upper threshold
- the sampling unit 15 When the time difference ⁇ t is greater than or equal to the first threshold TH1 and less than or equal to the second threshold TH2, that is, when the time difference ⁇ t falls within the determination range defined by the first threshold TH1 and the second threshold TH2 , the sampling unit 15 outputs the output voltage signal S13, which is the result of A/D conversion, assuming that the received quantum signal Q is a true quantum signal (step ST2 in FIG. 7).
- the sampling unit 15 determines that the received quantum signal Q is false. Assuming that it is a quantum signal, the signal is discarded without outputting the output voltage signal S13, which is the result of A/D conversion described above (step ST3 in FIG. 7).
- the timing of the output current from the photon detector in other words, the information on the photons entering the photon detector with a time lag of a certain amount or more can be discarded. It is possible to suitably prevent eavesdropping by a time shift attack that utilizes incident timing dependence.
- FIG. 8 shows the signal flow in the wiretapping prevention operation in the photon detection device 10 according to the first embodiment.
- FIG. 9 is a flow chart of wiretapping prevention operation in the photon detection device 10 according to the first embodiment.
- the signal processing section 16 performs predetermined signal processing on the output voltage signal S13 according to the clock signal CLK.
- the time from the time t when the quantum signal Q enters the APD 13 until the output voltage signal S13 reaches the signal processing section 16 is defined as ⁇ t d2 .
- the signal processing unit 16 monitors the time difference ⁇ t between the time t+ ⁇ t d2 at which the output voltage signal S13 reaches the signal processing unit 16 and the reference timing T ref . , time difference determination may be performed. Even in this case, it can be understood that the sampling unit 15 indirectly monitors the timing at which the output current I1 is output from the APD 13 by monitoring the time difference ⁇ t, as described above.
- the signal processing unit 16 monitors the time difference ⁇ t (also referred to as a second time difference) and determines whether the time difference ⁇ t is greater than or equal to the first threshold TH1 and less than or equal to the second threshold TH2 (see FIG. 9 step ST4).
- ⁇ t also referred to as a second time difference
- the signal processing unit 16 determines that the received quantum signal Q is true. , the signal processing unit 16 performs the above-described signal processing (step ST5 in FIG. 9).
- the signal processing unit 16 does not perform the above-described signal processing and discards the output voltage signal S13 (FIG. 9 step ST6).
- an avalanche photodiode is used as a single photon detector.
- a single photon detector may be applied.
- the time difference falls within the determination range when it is equal to or greater than the lower threshold of the determination range and equal to or less than the upper threshold of the determination range, but this is merely an example. For example, if the time difference is greater than the lower limit threshold of the determination range and smaller than the upper limit threshold, it may be determined to be within the determination range.
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Abstract
Description
実施の形態1にかかる量子鍵配送システム1000について説明する。量子鍵配送システム1000は、例えば、位相エンコード又は偏波エンコードのBB84プロトコルが適用されたものとして構成される。
なお、本発明は上記実施の形態に限られたものではなく、趣旨を逸脱しない範囲で適宜変更することが可能である。例えば、上述の実施の形態では、単一光子検出器としてアバランシェフォトダイオードを用いるものとして説明したが、光子検出効率が光子の入射タイミングに依存する単一光子検出器であるかぎり、他の構成の単一光子検出器を適用してもよい。
11、21 タイミング生成部
12、21 電源部
13 アバランシェフォトダイオード(APD)
14、23 電流電圧変換部
15 サンプリング部
16 信号処理部
20 同期信号受信装置
22 フォトダイオード
24 基準電圧生成部
30 クロック生成部
40 波長分離部
100 受信装置
110 送信装置
120、130 伝送路
1000 量子鍵配送システム
CLK クロック信号
I1、I2 出力電流
OUT 光子検出信号
Q 量子信号
REF 基準信号
S 同期信号
S11 逆バイアスパルスタイミング信号
S12、S13、S21 出力電圧信号
VB1、VB2 逆バイアス電圧
Claims (8)
- 量子信号の検出結果を示す電流信号を出力する光子検出器と、
前記電流信号を電圧信号に変換する電流電圧変換部と、
前記電圧信号をアナログ-デジタル変換した出力信号を出力するアナログ-デジタル変換器と、
前記出力信号に所定の信号処理を行って、前記量子信号の検出結果を示す検出信号を出力する信号処理部と、を備え、
前記光子検出器から前記電流信号が出力されるタイミングと、クロック信号に基づいて決定される基準タイミングと、の間の時間差が判定範囲に収まらない場合には、前記検出信号は前記信号処理部から出力されない、
光子検出装置。 - 前記アナログ-デジタル変換器は、
前記電流信号が入力するタイミングと、前記基準タイミングと、の間の第1の時間差が第1の判定範囲に収まる場合には、前記出力信号を前記信号処理部に出力し、
前記第1の時間差が前記第1の判定範囲に収まらない場合には、前記出力信号を破棄する、
請求項1に記載の光子検出装置。 - 前記信号処理部は、
前記出力信号が入力するタイミングと、前記基準タイミングと、の間の第2の時間差が第2の判定範囲に収まる場合には、前記検出信号を出力し、
前記第2の時間差が前記第2の判定範囲に収まらない場合には、前記検出信号を破棄する、
請求項1に記載の光子検出装置。 - 前記時間差が前記判定範囲の下限閾値以上かつ前記判定範囲の上限閾値以下の場合、前記時間差が前記判定範囲に収まるものと判定され、
前記時間差が前記判定範囲の前記下限閾値よりも小さい場合、又は、前記判定範囲の前記上限閾値よりも大きい場合、前記時間差が前記判定範囲に収まらないものと判定される、
請求項1乃至3のいずれか一項に記載の光子検出装置。 - 前記時間差が前記判定範囲の下限閾値よりも大きく、かつ、前記判定範囲の上限閾値よりも小さい場合、前記時間差が前記判定範囲に収まるものと判定され、
前記時間差が前記判定範囲の前記下限閾値以下の場合、又は、前記判定範囲の前記上限閾値以上の場合、前記時間差が前記判定範囲に収まらないものと判定される、
請求項1乃至3のいずれか一項に記載の光子検出装置。 - 量子信号を検出する光子検出装置を備え、
前記光子検出装置は、
前記量子信号の検出結果を示す電流信号を出力する光子検出器と、
前記電流信号を電圧信号に変換する電流電圧変換部と、
前記電圧信号をアナログ-デジタル変換した出力信号を出力するアナログ-デジタル変換器と、
前記出力信号に所定の信号処理を行って、前記量子信号の検出結果を示す検出信号を出力する信号処理部と、を備え、
前記光子検出器から前記電流信号が出力されるタイミングと、クロック信号に基づいて決定される基準タイミングと、の間の時間差が判定範囲に収まらない場合には、前記検出信号は前記信号処理部から出力されない、
受信装置。 - 量子信号を送信する送信装置と、
前記量子信号を検出する光子検出装置を備える受信装置と、を備え、
前記光子検出装置は、
前記量子信号の検出結果を示す電流信号を出力する光子検出器と、
前記電流信号を電圧信号に変換する電流電圧変換部と、
前記電圧信号をアナログ-デジタル変換した出力信号を出力するアナログ-デジタル変換器と、
前記出力信号に所定の信号処理を行って、前記量子信号の検出結果を示す検出信号を出力する信号処理部と、を備え、
前記光子検出器から前記電流信号が出力されるタイミングと、クロック信号に基づいて決定される基準タイミングと、の間の時間差が判定範囲に収まらない場合には、前記検出信号は前記信号処理部から出力されない、
量子鍵配送システム。 - 量子信号の検出結果を示す電流信号を出力し、
前記電流信号を電圧信号に変換し、
前記電圧信号をアナログ-デジタル変換した出力信号を出力し、
前記出力信号に所定の信号処理を行って、前記量子信号の検出結果を示す検出信号を出力し、
前記電流信号が出力されるタイミングと、クロック信号に基づいて決定される基準タイミングと、の間の時間差が判定範囲に収まらない場合には、前記検出信号は出力されない、
量子信号の検出方法。
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Publication number | Priority date | Publication date | Assignee | Title |
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JP2003037594A (ja) * | 2001-07-26 | 2003-02-07 | Mitsubishi Electric Corp | 光信号伝送装置及び光信号伝送システム及び光信号伝送方法 |
JP2008294934A (ja) * | 2007-05-28 | 2008-12-04 | Nippon Telegr & Teleph Corp <Ntt> | 量子暗号通信システムおよび盗聴検知方法 |
WO2019106971A1 (ja) * | 2017-11-30 | 2019-06-06 | 沖電気工業株式会社 | 単一光子検出装置及び量子鍵配送用受信装置 |
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JP2008294934A (ja) * | 2007-05-28 | 2008-12-04 | Nippon Telegr & Teleph Corp <Ntt> | 量子暗号通信システムおよび盗聴検知方法 |
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WO2019180770A1 (ja) * | 2018-03-19 | 2019-09-26 | 日本電気株式会社 | 光子検出器の駆動タイミング調整方法、装置および光通信システム |
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---|---|---|---|---|
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