The most important goal of quantum communication is to distribute the encryption key between the transmitter and the receiver. The optimal situation in Quantum Key Distribution (QKD) between transmitter and receiver is to increase the key distribution rate per second, increase the transmission distance, and reduce the error in key distribution. Several protocols used for QKD. The most important of QKD protocols is the BB84. One of the challenges leading to errors in quantum protocols is generating error pulses in single-photon detectors. These pulses caused by the inherent effects of quantum devices. They can cause wrong detection in the receiver. Many measures have been taken in the design and construction of single-photon detectors to reduce this error pulses, but it is not possible to eliminate all of them. Afterpulse and dark counts are two types of unwanted pulses that occur with single-photon detectors. In this paper, a new QKD protocol is proposed. It is an upgrade of the BB84 protocol and can reduce the effects of unwanted pulses such as afterpulse and dark counts in QKD avalanche detectors.
The most important goal of quantum communication is to distribute the encryption key between the transmitter and the receiver. The optimal situation in Quantum Key Distribution (QKD) between transmitter and receiver is to increase the key distribution rate per second, increase the transmission distance, and reduce the error in key distribution. Several protocols used for QKD. The most important of QKD protocols is the BB84. One of the challenges leading to errors in quantum protocols is generating error pulses in single-photon detectors. These pulses caused by the inherent effects of quantum devices. They can cause wrong detection in the receiver. Many measures have been taken in the design and construction of single-photon detectors to reduce this error pulses, but it is not possible to eliminate all of them. Afterpulse and dark counts are two types of unwanted pulses that occur with single-photon detectors. In this paper, a new QKD protocol is proposed. It is an upgrade of the BB84 protocol and can reduce the effects of unwanted pulses such as afterpulse and dark counts in QKD avalanche detectors.
A Single-Photon Avalanche Diode (SPAD) is a specialized optoelectronic device designed for the detection of single photons. It can discern the presence or absence of photons as well as their reception frequency. A significant challenge associated with SPADs is the generation of unintended pulses, which manifest in two primary categories: Dark Count Rate (DCR) and Afterpulse Probability (PAP). Dark counting refers to the occurrence of output pulses in the absence of photon detection, while afterpulse are undesirable outputs resulting from the trapping of carrier’s post-avalanche event within the detector. These trapped carriers are subsequently accelerated by the activation field applied to the detector, causing another avalanche breakdown known as an afterpulse. Both the afterpulse effect and dark counting are considered detrimental phenomena in SPADs, which are commonly utilized in Quantum Key Distribution (QKD) systems. Quantum Key Distribution is a cryptographic method for securely distributing secret keys, leveraging principles of quantum mechanics. Moreover, this method ensures that an eavesdropper cannot intercept or regenerate photon states. In this study, a novel approach is proposed to detect errors induced by these undesirable pulses in a quantum key distribution system. The proposed method, designed to mitigate the effects of unwanted pulses in QKD using the BB84 protocol, employs two quantum channels for photon transmission and a classical channel for coordination between the communicating parties and filtering the secret key (sifting). This method preserves the secure key rate when compared to the traditional BB84 protocol. The reduction of undesirable pulses in the proposed method is contingent upon factors such as the probability of afterpulse occurrence, dark count events, and the efficiency of the single-photon detector, with the reduction being computed in direct proportion to these parameters.
A Single-Photon Avalanche Diode (SPAD) is a specialized optoelectronic device designed for the detection of single photons. It can discern the presence or absence of photons as well as their reception frequency. A significant challenge associated with SPADs is the generation of unintended pulses, which manifest in two primary categories: Dark Count Rate (DCR) and Afterpulse Probability (PAP). Dark counting refers to the occurrence of output pulses in the absence of photon detection, while afterpulse are undesirable outputs resulting from the trapping of carrier’s post-avalanche event within the detector. These trapped carriers are subsequently accelerated by the activation field applied to the detector, causing another avalanche breakdown known as an afterpulse. Both the afterpulse effect and dark counting are considered detrimental phenomena in SPADs, which are commonly utilized in Quantum Key Distribution (QKD) systems. Quantum Key Distribution is a cryptographic method for securely distributing secret keys, leveraging principles of quantum mechanics. Moreover, this method ensures that an eavesdropper cannot intercept or regenerate photon states. In this study, a novel approach is proposed to detect errors induced by these undesirable pulses in a quantum key distribution system. The proposed method, designed to mitigate the effects of unwanted pulses in QKD using the BB84 protocol, employs two quantum channels for photon transmission and a classical channel for coordination between the communicating parties and filtering the secret key (sifting). This method preserves the secure key rate when compared to the traditional BB84 protocol. The reduction of undesirable pulses in the proposed method is contingent upon factors such as the probability of afterpulse occurrence, dark count events, and the efficiency of the single-photon detector, with the reduction being computed in direct proportion to these parameters.
The afterpulse effect is an undesirable phenomenon that occurs in single-photon avalanche diodes (SPADs). SPADs are widely employed in quantum key distribution (QKD) systems. As QKD systems advance to support higher data rates, the minimization of afterpulses becomes increasingly critical. In this paper, we introduce new structure for BB84 QKD protocol to reduce afterpulses in QKD systems. The proposed method does not change secure key rate compared to the conventional BB84 protocol. We conduct a theoretical analysis and simulation of the performance of a single-photon-based QKD system utilizing SPADs with suboptimal afterpulse characteristics. Our results indicate that the afterpulse probability (Pa) in SPADs does not impose a strict lower bound on the error rate of sifted keys in single-photon-based QKD systems. The system utilizes a simplified version of the two-bases BB84 protocol, which operates over fiber-optic or free-space channels. In the proposed structure, eight detectors are used to measure four polarization angles, yielding four possible outcomes. The findings emphasize the practicality of this setup for both fiber-based and free-space quantum communication, making it highly suitable for real-world applications. The afterpulse decay is dependent on an exponential function and changes proportionally to the elapsed time, the number of trapped carriers, the carrier lifetime, the field strength, and the temperature. The project team has extensive experience in afterpulse reduction and has published several papers on the subject. Using the idea presented in this paper, by doubling the receiver detectors under the same conditions, the probability of afterpulse occurrence is approximately halved. We are looking to propose new structures and protocols to reduce undesired pulses in single-photon avalanche detectors.
The afterpulse effect is an undesirable phenomenon that occurs in single-photon avalanche diodes (SPADs). SPADs are widely employed in quantum key distribution (QKD) systems. As QKD systems advance to support higher data rates, the minimization of afterpulses becomes increasingly critical. In this paper, we introduce new structure for BB84 QKD protocol to reduce afterpulses in QKD systems. The proposed method does not change secure key rate compared to the conventional BB84 protocol. We conduct a theoretical analysis and simulation of the performance of a single-photon-based QKD system utilizing SPADs with suboptimal afterpulse characteristics. Our results indicate that the afterpulse probability (Pa) in SPADs does not impose a strict lower bound on the error rate of sifted keys in single-photon-based QKD systems. The system utilizes a simplified version of the two-bases BB84 protocol, which operates over fiber-optic or free-space channels. In the proposed structure, eight detectors are used to measure four polarization angles, yielding four possible outcomes. The findings emphasize the practicality of this setup for both fiber-based and free-space quantum communication, making it highly suitable for real-world applications. The afterpulse decay is dependent on an exponential function and changes proportionally to the elapsed time, the number of trapped carriers, the carrier lifetime, the field strength, and the temperature. The project team has extensive experience in afterpulse reduction and has published several papers on the subject. Using the idea presented in this paper, by doubling the receiver detectors under the same conditions, the probability of afterpulse occurrence is approximately halved. We are looking to propose new structures and protocols to reduce undesired pulses in single-photon avalanche detectors.
The afterpulse effect is an undesirable phenomenon that occurs in single-photon avalanche diodes (SPADs). SPADs are widely employed in quantum key distribution (QKD) systems. As QKD systems advance to support higher data rates, the minimization of afterpulses becomes increasingly critical. In this paper, we introduce new structure for BB84 QKD protocol to reduce afterpulses in QKD systems. The proposed method does not change secure key rate compared to the conventional BB84 protocol. We conduct a theoretical analysis and simulation of the performance of a single-photon-based QKD system utilizing SPADs with suboptimal afterpulse characteristics. Our results indicate that the afterpulse probability (Pa) in SPADs does not impose a strict lower bound on the error rate of sifted keys in single-photon-based QKD systems. The system utilizes a simplified version of the two-bases BB84 protocol, which operates over fiber-optic or free-space channels. In the proposed structure, eight detectors are used to measure four polarization angles, yielding four possible outcomes. The findings emphasize the practicality of this setup for both fiber-based and free-space quantum communication, making it highly suitable for real-world applications. The afterpulse decay is dependent on an exponential function and changes proportionally to the elapsed time, the number of trapped carriers, the carrier lifetime, the field strength, and the temperature. The project team has extensive experience in afterpulse reduction and has published several papers on the subject. Using the idea presented in this paper, by doubling the receiver detectors under the same conditions, the probability of afterpulse occurrence is approximately halved. We are looking to propose new structures and protocols to reduce undesired pulses in single-photon avalanche detectors.
The afterpulse effect is an undesirable phenomenon that occurs in single-photon avalanche diodes (SPADs). SPADs are widely employed in quantum key distribution (QKD) systems. As QKD systems advance to support higher data rates, the minimization of afterpulses becomes increasingly critical. In this paper, we introduce what we believe to be a new structure for the BB84 QKD protocol to reduce afterpulses in QKD systems. The proposed method does not change the secure key rate compared to the conventional BB84 protocol. We conduct a theoretical analysis and simulation of the performance of a single-photon-based QKD system utilizing SPADs with suboptimal afterpulse characteristics. Our results indicate that the afterpulse probability (Pa) in SPADs does not impose a strict lower bound on the error rate of sifted keys in single-photon-based QKD systems. The system utilizes a simplified version of the two-bases BB84 protocol, which operates over fiber-optic or free-space channels. In the proposed structure, eight detectors are used to measure four polarization angles, yielding four possible outcomes. The findings emphasize the practicality of this setup for both fiber-based and free-space quantum communication, making it highly suitable for real-world applications. The afterpulse decay is dependent on an exponential function and changes proportionally to the elapsed time, the number of trapped carriers, the carrier lifetime, the field strength, and the temperature. The project team has extensive experience in afterpulse reduction and has published several papers on the subject. Using the idea presented in this paper, by doubling the receiver detectors under the same conditions, the probability of afterpulse occurrence is approximately halved. We are looking to propose new structures and protocols to reduce undesired pulses in single-photon avalanche detectors.