We demonstrate integrated photonic circuits for quantum devices using sputtered polycrystalline aluminum nitride(Al N)on insulator.On-chip Al N waveguide directional couplers,which are one of the most important compon...We demonstrate integrated photonic circuits for quantum devices using sputtered polycrystalline aluminum nitride(Al N)on insulator.On-chip Al N waveguide directional couplers,which are one of the most important components in quantum photonics,are fabricated and show the output power splitting ratios from 50:50 to 99:1.Polarization beam splitters with an extinction ratio of more than 10 d B are also realized from the Al N directional couplers.Using the fabricated Al N waveguide beam splitters,we observe Hong–Ou–Mandel interference with a visibility of 91.7%±5.66%.展开更多
Quantum key distribution(QKD)networks constitute promising solutions for secure communication.Beyond conventional point-to-point QKD,we developed 1×N QKD network systems with a sub-nanosecond resolution optical p...Quantum key distribution(QKD)networks constitute promising solutions for secure communication.Beyond conventional point-to-point QKD,we developed 1×N QKD network systems with a sub-nanosecond resolution optical path length compensation scheme.With a practical plug-and-play QKD architecture and compact timing control modules based on a field-programmable gate array,we achieved long-term stable operation of a 1×64 QKD network system.Using this architecture,64 users can simultaneously share secret keys with one server,without using complex software algorithms and expensive hardware.We demonstrated the workings of a 1×4 QKD network system using the fiber network of a metropolitan area.展开更多
We develop a quantum key distribution (QKD) system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a plug-and-play QKD ...We develop a quantum key distribution (QKD) system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a plug-and-play QKD system. The system monitors changes in key rates and controls it is own operation automatically. The system achieves its optimal performance within three seconds of operation, which includes a sifted key rate of 5.5 kbps and a quantum bit error rate of less than 2% after an abrupt temperature variation along the 25 km quantum channel. The system also operates well over a 24 h period while completing more than 60 active optical path length compensations.展开更多
基金Korea Institute of Science and Technology (2E32241,2E32801)National Research Council of Science and Technology (CAP21031-200)+1 种基金Institute for Information and Communications Technology Promotion (2020-0-00947,2020-0-00972)National Research Foundation of Korea (2019M3E4A1079777,2021M1A2A2043892).
文摘We demonstrate integrated photonic circuits for quantum devices using sputtered polycrystalline aluminum nitride(Al N)on insulator.On-chip Al N waveguide directional couplers,which are one of the most important components in quantum photonics,are fabricated and show the output power splitting ratios from 50:50 to 99:1.Polarization beam splitters with an extinction ratio of more than 10 d B are also realized from the Al N directional couplers.Using the fabricated Al N waveguide beam splitters,we observe Hong–Ou–Mandel interference with a visibility of 91.7%±5.66%.
基金National Research Foundation of Korea(2019M3E4A107866011,2019M3E4A1079777,2019R1A2C2006381)Korea Institute of Science and Technology(2E29580)+1 种基金ICT Research and Development Programs of MSIP/IITP(2014-3-00524)We thank the KT Corporation forproviding their deployed fiber.
文摘Quantum key distribution(QKD)networks constitute promising solutions for secure communication.Beyond conventional point-to-point QKD,we developed 1×N QKD network systems with a sub-nanosecond resolution optical path length compensation scheme.With a practical plug-and-play QKD architecture and compact timing control modules based on a field-programmable gate array,we achieved long-term stable operation of a 1×64 QKD network system.Using this architecture,64 users can simultaneously share secret keys with one server,without using complex software algorithms and expensive hardware.We demonstrated the workings of a 1×4 QKD network system using the fiber network of a metropolitan area.
基金was supported by the ICT R&D programs of Ministry of Science, ICT and Future Planning/Institute for Information & Communications Technology Promotion (Grant No. B0101-16-1355)the Korea Institute of Science and Technology research program (Grant No. 2E27231)Korea Institute of Science and Technology-Electronics And Telecommunications Research Institute research program (Grant No. 2V05340)
文摘We develop a quantum key distribution (QKD) system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a plug-and-play QKD system. The system monitors changes in key rates and controls it is own operation automatically. The system achieves its optimal performance within three seconds of operation, which includes a sifted key rate of 5.5 kbps and a quantum bit error rate of less than 2% after an abrupt temperature variation along the 25 km quantum channel. The system also operates well over a 24 h period while completing more than 60 active optical path length compensations.
