Shapiro Steps in Flux-Trapped Surface Intrinsic Junctions of Bi2Sr2CaCu2O8+δ
WEI Yan-Feng1, ZHAO Shi-Ping1, ZHU Xiao-Bo1, CHEN Geng-Hua1, REN Yu-Feng1, YU Hong-Wei1, YANG Qian-Sheng1, HU Yun2
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080
2Department of Physics, University of Science and Technology of China, Hefei 230026
Shapiro Steps in Flux-Trapped Surface Intrinsic Junctions of Bi2Sr2CaCu2O8+δ
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080
2Department of Physics, University of Science and Technology of China, Hefei 230026
Abstract： Microwave-field responses of the surface intrinsic Josephson junctions (IJJs) of Bi2Sr2CaCu2O8+δ superconductors are investigated. The IJJs are fabricated using an in situ low-temperature cleavage technique, which leads to the well-characterized surface CuO2 double layers and surface junctions. For the surface junctions in the large-junction limit, usually no Shapiro steps appear when a microwave field is applied. It is found that when the junctions are in a flux-trapped state, which is produced by a pulsed current and in which the critical current is significantly suppressed, clear Shapiro steps can be observed. These results are important for the study of the microwave-field properties of vortex-carrying IJJs and may find their use in device applications.
2005, Vol. 22 
