公开(公告)号：US09722785B2

公开(公告)日：2017-08-01

申请号：US14590585

申请日：2015-01-06

Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY

Inventor： Yong-Su Kim ,  Sang Wook Han ,  Sung Wook Moon ,  Yujun Choi

IPC: H04L9/08 ,  H04B10/70

CPC classification number: H04L9/0855 ,  H04B10/70 ,  H04L2209/34

Abstract: An apparatus for quantum cryptographic communication includes a light source configured to generate an optical pulse which is transmitted to a plurality of quantum code sending devices, and a quantum entanglement measuring unit configured to receive the optical signal generated from each of the plurality of quantum code sending devices and measure a relation among quantum states of the optical signals received from the plurality of quantum code sending devices; the optical signal being generated by encoding a key to a quantum state of the optical pulse. The apparatus for quantum cryptographic communication may further include a signal direction determining unit, a reflector for reflecting the optical pulse or the optical signal, an arbitrary phase shifter, or a modulator for encoding a digital signal corresponding to the key to the optical pulse.

公开(公告)号：US11598905B2

公开(公告)日：2023-03-07

申请号：US16897024

申请日：2020-06-09

Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY

Inventor： Sang Wook Han ,  Seung Woo Jeon ,  Sung Wook Moon ,  Yong Su Kim ,  Hyang Tag Lim ,  Ho Joong Jung ,  Young Wook Cho

IPC: G02B3/00 ,  C09K11/65 ,  B82Y40/00 ,  B82Y20/00 ,  B82Y30/00

Abstract: An inverted nanocone structure of the present disclosure includes a first surface, a second surface spaced apart from the first surface by a predetermined distance and having a greater area than the first surface, and a body having an inverted cone shape between the first surface and the second surface, wherein at least one activated point defect center is provided in the body.

公开(公告)号：US11528133B2

公开(公告)日：2022-12-13

申请号：US16739526

申请日：2020-01-10

Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY

Inventor： Sang Wook Han ,  Sung Wook Moon ,  Yong Su Kim ,  Sang Yun Lee ,  Young Wook Cho ,  Min Sung Kang ,  Ji Woong Choi

IPC: H04L9/08

Abstract: This specification discloses a quantum public-key cryptosystem. The quantum public-key cryptosystem may use two rotation operators R{circumflex over (n)}(θ) and R{circumflex over (m)}(φ) satisfying a cyclic evolution. The two rotation operators R{circumflex over (n)}(θ) and R{circumflex over (m)}(φ) do not have a commutation relation or an anti-commutation relation with each other. The commutation relation or the anti-commutation relation is established when either of the following conditions is satisfied: θ=2iπ, φ=2jπ, or {circumflex over (n)}·{circumflex over (m)}=1 (i, j=integer), and θ=(2k+1)π, φ=(2l+1)π, or {circumflex over (n)}·{circumflex over (m)}=0 (k, l=integer).

公开(公告)号：US10110378B2

公开(公告)日：2018-10-23

申请号：US15176428

申请日：2016-06-08

Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY

Inventor： Sang Wook Han ,  Sung Wook Moon ,  Yong-Su Kim ,  Il Young Kim ,  Byungkwon Park

IPC: H04L9/08 ,  B82Y20/00 ,  H04B10/70

Abstract: Disclosed is a method for stabilizing a quantum cryptography system, which includes: determining whether the quantum cryptography system operates in a stabilized state, on the basis of a bit error rate or a key rate of the quantum cryptography system; and readjusting an arrival time of a gate pulse or a laser operation time so that an arrival time of a single photon for a photon detector is aligned with the arrival time of the gate pulse, when the quantum cryptography system does not operate in a stabilized state. Here, the quantum cryptography system may be a two-way quantum cryptography system.

公开(公告)号：US10142033B2

公开(公告)日：2018-11-27

申请号：US15357424

申请日：2016-11-21

Applicant: Korea Institute of Science and Technology

Inventor： Sang Wook Han ,  Sung Wook Moon ,  Yong Su Kim ,  Min Ki Woo

IPC: H04B10/70 ,  H04B10/85 ,  H04L9/08 ,  H04L7/00

Abstract: Disclosed is a communication apparatus including a synchronization signal detector configured to detect a synchronization signal received from other communication apparatus coupled to the communication apparatus, wherein the other communication apparatus sends a quantum signal generated by a first light source to the communication apparatus, and a second light source configured to generate a decoy signal to be added to a quantum signal that is to be sent to the other communication apparatus according to a result of the detection of the synchronization signal.

公开(公告)号：US10936287B2

公开(公告)日：2021-03-02

申请号：US16335039

申请日：2017-09-26

Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY

Inventor： Sang Wook Han ,  Sung Wook Moon ,  Yong Su Kim ,  Byung Kwon Park

IPC: G06F7/58 ,  G06F16/51 ,  H04N5/357 ,  H04N5/372 ,  H04N5/374

Abstract: The present invention provides a random number generation system comprising: an image sensor module for outputting dark noise generated from each unit pixel region respectively that is shielded from external light as digital data; and a control unit for classifying the respective pieces of digital data output from the image sensor module, for allocating random numbers to the same using a database in which a plurality of reference values are stored for each unit pixel, and for collating the same so as to generate a first random number.