Multimode operation of a superconducting nanowire switch in the nanosecond regime

TL;DR

This paper demonstrates fast, nanosecond-scale switching of a superconducting nanowire device using gate voltages, introducing a novel operation mode that enhances speed and potential for low-power applications.

Contribution

It presents a new switching mechanism based on displacement current, achieving faster transition times than traditional leakage-based methods in superconducting nanowire switches.

Findings

Switching times of 1-2 ns to normal state

Faster switching (4-6 ns) in the reverse transition

Potential for low-power, high-speed superconducting devices

Abstract

Superconducting circuits are promising candidates for future computational architectures, however, practical applications require fast operation. Here, we demonstrate fast, gate-based switching of an Al nanowire-based superconducting switch in time-domain experiments. We apply voltage pulses on the gate while monitoring the microwave transmission of the device. Utilizing the usual leakage-based operation these measurements yield a fast, 1--2~ns switching time to the normal state, possibly limited by the bandwidth of our setup, and a 10--20~ns delay in the normal to superconducting transition. However, having a significant capacitance between the gate and the device allows for a novel operation, where the displacement current, induced by the fast gate pulses, drives the transition. The switching from superconducting to the normal state yields a similar fast timescale, while in the opposite direction the switching is significantly faster (4--6~ns) than the leakage based operation, which may be further improved by better thermal design. The measured short timescales and novel switching operation open the way for future fast and low-power-consumption applications.