公开(公告)号：US20240297722A1

公开(公告)日：2024-09-05

申请号：US18682917

申请日：2022-08-12

Applicant: QUDOOR TECHNOLOGIES INC.

Inventor： Liuping CHEN ,  Yongsheng FAN ,  Qibing WANG ,  Xiangkui WAN ,  Nan LI ,  Zhenyang JIN

IPC: H04B10/70 ,  G01J1/44 ,  H04L9/08

CPC classification number: H04B10/70 ,  G01J1/44 ,  H04L9/0858 ,  G01J2001/442 ,  G01J2001/444

Abstract: The disclosure provides a gating apparatus for a single-photon detector and a quantum communication device. The gating apparatus includes: a system synchronization unit, configured to obtain a periodic gating signal synchronized with a clock of a quantum communication system; a clock distributor, configured to divide the periodic gating signal into two periodic gating signals; a delay unit, configured to delay one periodic gating signal of the two periodic gating signals, so that the one periodic gating signal and the other periodic gating signal of the two periodic gating signals are spaced apart by predetermined duration; and a logical OR gate, configured to perform an OR operation on the one periodic gating signal delayed and the other periodic gating signal undelayed of the two periodic gating signals, so as to generate a periodic gating signal sequence synchronized with the clock of the quantum communication system.

公开(公告)号：US20240372630A1

公开(公告)日：2024-11-07

申请号：US18682915

申请日：2022-08-12

Applicant: QUDOOR TECHNOLOGIES INC.

Inventor： Liuping CHEN ,  Yongsheng FAN ,  Xiangkui WAN ,  Zhenyang JIN ,  Qibing WANG ,  Xihui YANG

IPC: H04B10/70

Abstract: Provided in the present disclosure are a gating apparatus for a single-photon detector, and a quantum communication device. The gating apparatus comprises: a system synchronization unit configured to acquire a clock of a quantum communication system; and a programmable controller configured to generate at least one periodic gating signal sequence that are synchronized with the clock of the quantum communication system, wherein gating signals in each gating signal sequence are spaced apart from each other by a predetermined duration, such that a single-photon detector can operate in a corresponding Geiger mode for a received optical pulse, and the predetermined duration is an optical path difference between a long arm and a short arm of an unequal-arm interferometer that is used for performing phase encoding in the quantum communication system.

公开(公告)号：US20240411273A1

公开(公告)日：2024-12-12

申请号：US18701547

申请日：2022-08-30

Applicant: QUDOOR TECHNOLOGIES INC.

Inventor： Liuping CHEN ,  Yongsheng FAN ,  Renqing FU ,  Guofeng ZHANG ,  Xiangkui WAN ,  Jian ZHANG

IPC: G04F10/00 ,  H04B10/70

Abstract: A method and apparatus for measuring time, and a programmable controller for a quantum communication device are provided. The method includes: receiving a START signal and a STOP signal; sampling the START signal and the STOP signal by using a same clock to generate a START bit string corresponding to the START signal and a STOP bit string corresponding to the STOP signal; extracting a rising edge of the START signal from the START bit string, and extracting a rising edge of the STOP signal from the STOP bit string; and determining a time interval between the START signal and the STOP signal based on a count of bits between the rising edge of the START signal and the rising edge of the STOP signal and based on a period of the clock.

公开(公告)号：US20240377251A1

公开(公告)日：2024-11-14

申请号：US18684686

申请日：2022-08-12

Applicant: QUDOOR TECHNOLOGIES INC.

Inventor： Liuping CHEN ,  Yongsheng FAN ,  Liting TONG ,  Xiangsheng SHE ,  Nan LI ,  Qibing WANG ,  Xiangkui WAN

IPC: G01J1/44 ,  H01L31/107

Abstract: The disclosure provides a method and apparatus for extracting an avalanche signal. The method includes: obtaining an avalanche photodiode (APD) signal output by a single-photon detector, wherein the APD signal comprises an upper spike and a lower spike, the upper spike is generated along with a rising edge of a gating signal, and the lower spike is generated along with a falling edge of the gating signal; determining a delay position of the upper spike in the APD signal, so as to determine a delay position of the lower spike in the APD signal based on a pulse width of the gating signal; shifting a coincidence gate signal, so as to align a delay position of a falling edge of the coincidence gate signal with the delay position of the lower spike in the APD signal, wherein a pulse width of the coincidence gate signal is smaller than the pulse width of the gating signal; and extracting, as the avalanche signal, a second pulse that is generated through an AND operation on a first pulse that is generated by a partial signal, exceeding a discrimination threshold, in the APD signal and the coincidence gate signal.