Fast switching current detection at low critical currents

TL;DR

This paper introduces a pulse-and-hold measurement method for small critical current Josephson junctions, enabling accurate detection and probability measurement at very low currents and short pulse durations.

Contribution

The paper presents a novel pulse-and-hold technique that improves switching detection in small Josephson junctions, overcoming previous limitations of simple pulse methods.

Findings

Effective detection of junctions with ~10nA critical currents

Ability to measure switching probabilities with ~100ns pulses

Correlation analysis reveals dependence of switching on wait time

Abstract

A pulse-and-hold technique is used to measure the switching of small critical current Josephson junctions. This technique allows one to achieve a good binary detection and therefore measure switching probabilities. The technique overcomes limitations on simple square pulses and allows for the measurement of junctions with critical currents of the order of 10nA with bias pulses of the order of 100ns. A correlation analysis of the switching events is performed to show how the switching probability depends on the wait time between repeated bias pulses.