Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.
Science. 2021 Apr 23;372(6540):409-412. doi: 10.1126/science.abf5539.
Josephson junctions are superconducting devices used as high-sensitivity magnetometers and voltage amplifiers as well as the basis of high-performance cryogenic computers and superconducting quantum computers. Although device performance can be degraded by the generation of quasiparticles formed from broken Cooper pairs, this phenomenon also opens opportunities to sensitively detect electromagnetic radiation. We demonstrate single near-infrared photon detection by coupling photons to the localized surface plasmons of a graphene-based Josephson junction. Using the photon-induced switching statistics of the current-biased device, we reveal the critical role of quasiparticles generated by the absorbed photon in the detection mechanism. The photon sensitivity will enable a high-speed, low-power optical interconnect for future superconducting computing architectures.
约瑟夫森结是超导器件，可用作高灵敏度磁强计和电压放大器，也是高性能低温计算机和超导量子计算机的基础。尽管器件性能可能因形成于被破坏的库珀对的准粒子的产生而降低，但这一现象也为灵敏地探测电磁辐射开辟了机会。我们通过将光子耦合到基于石墨烯的约瑟夫森结的局域表面等离激元，实现了单个近红外光子的探测。利用该电流偏置器件中光子诱导的开关统计数据，我们揭示了被吸收光子产生的准粒子在探测机制中所起的关键作用。这种光子灵敏度将为未来超导计算架构提供高速、低功耗的光互连。
