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Physical review. B, Condensed matter

Thermal escape from zero-voltage states in hysteretic superconducting interferometers

Niels Grønbech‐Jensen, Daniel B. Thompson, Matteo Cirillo, C. Cosmelli

Published Jun 13, 2003• 17 citations
Publisher

Abstract

We analyze the thermal escape behavior of the metastable zero-voltage state in biased symmetric hysteretic interferometers in external magnetic fields. An effective single degree of freedom equation of motion for the system with small loop inductance is derived and used to evaluate the two necessary parameters, energy barrier and attempt frequency, for the successful application of Kramers theory for thermal escape from metastable states. The slightly revised theory, resulting in a double pendulum model of the interferometer, is outlined and numerical simulation results are used to validate the approach. Recent experimental reports of excessive thermal escape temperatures for interferometers are discussed and interpreted.

DOI
10.1103/physrevb.67.224505

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