Hysteresis and intermittency in a nano-bridge based suspended DC-SQUID

TL;DR

This paper investigates the voltage behavior of a nano-bridge based DC-SQUID on a Si3N4 membrane, revealing hysteresis and intermittency effects influenced by thermal coupling and magnetic flux, with implications for noise reduction.

Contribution

It introduces a study of hysteresis and intermittency in nano-bridge DC-SQUIDs on membranes, highlighting effects of thermal coupling and flux-dependent voltage patterns.

Findings

Strong hysteretic voltage response due to poor thermal coupling.

Intermittent voltage patterns near oscillation thresholds influenced by magnetic flux.

Potential for noise reduction by substrate engineering.

Abstract

We study voltage response of nano-bridge based DC-SQUID fabricated on a Si\_{3}N\_{4} membrane. Such a configuration may help in reducing 1/f noise, which originates from substrate fluctuating defects. We find that the poor thermal coupling between the DC-SQUID and the substrate leads to strong hysteretic response of the SQUID, even though it is biased by an alternating current. In addition, when the DC-SQUID is biased near a threshold of spontaneous oscillations, the measured voltage has an intermittent pattern, which depends on the applied magnetic flux through the SQUID.