Observation of superconductivity in granular bi nanowires fabricated by electrodeposition.
Bulk rhombohedral Bi at ambient pressure is a well-known semimetal, and its transition to a superconductor has not been observed, at least down to 50 mK. We report that, unlike bulk rhombohedral Bi, granular Bi nanowires with well-defined rhombohedral grains of approximately 10 nm diameter, fabricated by electrochemically depositing Bi into porous polycarbonate membranes at ambient pressure, are superconducting with two transition temperatures, Tc, of 7.2 and 8.3 K. These Tc values coincide with Tc values of the high-pressure phases Bi-III and Bi-V, respectively. Analysis of our structural and transport data indicates that the superconductivity in granular Bi nanowires probably arises from grain boundary areas where there are structural reconstructions between the grains showing a preferred orientation within a small angular distribution.
Tian
Mingliang
M
Center for Nanoscale Science (CNS), Pennsylvania State University, University Park, Pennsylvania 16802-6300, USA. mut1@psu.edu
Wang
Jinguo
J
Kumar
Nitesh
N
Han
Tianheng
T
Kobayashi
Yoji
Y
Liu
Ying
Y
Mallouk
Thomas E
TE
Chan
Moses H W
MH