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Japanese Journal of Applied Physics

Enhanced AC Josephson Effect in YBa2Cu3O7-δ Junctions Driven by Two RF Sources

Cornelis Koster, Jian Chen, Hiroaki Myoren, Kensuke Nakajima, Tsutomu Yamashita, Akio Takada

Published Aug 1, 1998• 0 citations
Publisher

Abstract

Enhanced AC Josephson effect for YBa2Cu3O7-δ grain boundary Josephson junctions driven by two rf sources has been demonstrated. Maximum heights of the first Shapiro step have been obtained and are in good agreement with simulations based on the resistively shunted junction (RSJ) model.
DOI
10.1143/jjap.37.4356

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We observed the ac Josephson effect, the ‘‘Shapiro step,’’ at the high frequency of 584 GHz in an YBa2Cu3O7−δ grain boundary Josephson junction at 4.2 K for the first time. This Shapiro step grew to about 8% of the critical current without irradiation. We also noted that the critical current was gradually suppressed with increasing power. The critical current with irradiation was suppressed to about 97% of the critical current without irradiation. Detailed investigation revealed the consistency between the above two phenomena.
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