公开(公告)号：US12074970B2

公开(公告)日：2024-08-27

申请号：US17615375

申请日：2020-06-17

Applicant: KT CORPORATION

Inventor： Jeonghwan Shin ,  Kyung-Woon Lee ,  Min Soo Lee

IPC: H04L9/08 ,  G02B5/30 ,  G02B27/28 ,  H04B10/532 ,  H04B10/70

CPC classification number: H04L9/0858 ,  G02B5/3025 ,  G02B27/283 ,  H04B10/532 ,  H04B10/70 ,  H04L9/0827 ,  G02B27/286 ,  H04L9/0852

Abstract: Provided are a quantum key distribution method, device, and system. The quantum key distribution system may include a transmitter configured to split an optical signal into a first optical signal passing through a first path (P1) and a second optical signal passing through a second path (P2), which is longer than the first path (P1), and to sequentially transmit the first optical signal and the second optical signal; and a receiver configured to receive the first optical signal and the second optical signal incident through a quantum channel and transmit the first optical signal and the second optical signal back to the transmitter through the quantum channel after passing through a polarization-dependent element, being reflected by a Faraday mirror, and passing through the polarization-dependent element again.

公开(公告)号：US12038324B2

公开(公告)日：2024-07-16

申请号：US18031985

申请日：2021-10-08

Applicant: KT CORPORATION

Inventor： Min Soo Lee ,  Jeonghwan Shin ,  Kyung-Woon Lee

IPC: G01J1/44 ,  H04B10/70

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

Abstract: Provided are a single photon detector and an operation method thereof. The single photon detector may include a gate signal generator for generating a gate signal having a first pulse width (ΔP) with respect to a first time point (t1); and a first photon detector for detecting the single photon while operating in a Geiger mode by receiving the gate signal, and outputs a photon detection signal at a second time point (t2), wherein the first photon detector outputs the photon detection signal at the second time point (t2) spaced apart at a predetermine time interval (ΔT) from the first time point (t1).