A superconducting nanowire binary shift register

Abstract

We present a design for a superconducting nanowire binary shift register, which stores digital states in the form of circulating supercurrents in high-kinetic-inductance loops. Adjacent superconducting loops are connected with nanocryotrons, three-terminal electrothermal switches, and fed with an alternating two-phase clock to synchronously transfer the digital state between the loops. A two-loop serial-input shift register was fabricated with thin-film NbN and a bit error rate of less than 10−4 was achieved, when operated at a maximum clock frequency of [Formula: see text] and in an out-of-plane magnetic field of up to [Formula: see text]. A shift register based on this technology offers an integrated solution for low-power readout of superconducting nanowire single photon detector arrays and is capable of interfacing directly with room-temperature electronics and operating unshielded in high magnetic field environments.

Molybdenum Silicide Superconducting Nanowire Single-Photon Detectors on Lithium Niobate Waveguides

“…These characteristics are well suited for realizing and integrating other superconducting devices with no strict requirements on cooling and operation temperatures. These include digital, − and microwave electronic devices. Their monolithic integration with SNSPDs could lead to the realization of comprehensive circuits for on-chip quantum information processing, realizing the full potentials of integrated quantum photonics. , …”