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International Journal of Modern Physics B

MACROSCOPIC QUANTUM COHERENCE IN JOSEPHSON SYSTEMS

B. Ruggiero, Valentina Corato, E. Esposito, C. Granata, M. Russo, P. Silvestrini, Leo Stodolsky

Published Oct 30, 2000• 4 citations
Publisher

Abstract

We present our recent experiments on macroscopic tunneling in the quantum regime for underdamped Josephson junctions with different classical-quantum crossover temperatures. These experiments are performed towards the observation of macroscopic quantum coherence in Josephson systems. A new method to measure coherence in a two-level system based on the adiabatic inversion in an rf squid, is presented. This approach could open new perspectives in view of realization of an elementary quantum bit.

DOI
10.1142/s0217979200003290

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