Design Space Analysis of Superconducting Nanowire-based Cryogenic Oscillators

Abstract

Superconducting (SC) devices and circuits have been garnering immense interest in recent years. due to the emergence of several major applications that demand and justify cryogenic (cryo) cooling below 4 Kelvin temperature. Superconducting single flux quantum (SFQ) technology supports ultra-fast (hundreds of GHz) classical computing operations, far beyond the capabilities of the CMOS processors [1]. The energy demand of a recent prototype of a SC processor proved to be ~80X less than that of its semiconductor counterpart (considering cooling cost) [2]. SC devices/circuits have been used in several spacecrafts in the last few years [3]. The need to explore design prospects for SC devices/circuits has become more imperative. A Superconducting nanowire (ScNW) [4], [5] is among the most promising SC devices with possible applications in several avenues of cryogenic electronics. Recent demonstrations proved that the ScNWs can be utilized to design cryogenic oscillators [6], with possible usage in cryo-neuromorphic systems [7]. The dynamics of the ScNW oscillator is unlike any other non-SC oscillator. Hence, a systematic design space expiration is crucial to facilitate the adoption and incorporation of these unique oscillators in different avenues of cryo-electronics. In this work, we conduct a simulation-based study of the ScNW oscillators to identify the material/device-circuit co-design opportunities.