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Superconductor Science and Technology

Observation of macroscopic quantum tunnelling in a rf superconducting quantum interference device system

Valentina Corato, S. Rombetto, P. Silvestrini, C. Granata, Roberto Russo, B. Ruggiero

Published Apr 15, 2004• 9 citations
Publisher

Abstract

We present the experimental observation of the effects of macroscopic quantum tunnelling in a SQUID device, consisting of a rf SQUID coupled to a readout system based on a dc SQUID sensor. Data on the decay rate from the metastable flux states of a rf SQUID are reported, both in the classical and quantum regimes. The low dissipation level and the good insulation of the probe from external noise are encouraging in view of building a macroscopic quantum coherent system.

DOI
10.1088/0953-2048/17/5/059

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