Open AccessDramatic enhancement of superconductivity in single-crystalline nanowire arrays of Sn
Author(s) -
Ying Zhang,
Chi Hang Wong,
Junying Shen,
Sin Ting Sze,
Bing Zhang,
Haijing Zhang,
Dong Yan,
Hui Xu,
Yan Zhang,
Yingying Li,
Xijun Hu,
Rolf Lortz
Publication year - 2016
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/srep32963
Subject(s) - superconductivity , condensed matter physics , critical field , nanowire , resistive touchscreen , volume fraction , materials science , phase transition , phase (matter) , specific heat , surface (topology) , transition temperature , layer (electronics) , nanotechnology , physics , quantum mechanics , composite material , mathematics , geometry , engineering , electrical engineering
Sn is a classical superconductor on the border between type I and type II with critical temperature of 3.7 K. We show that its critical parameters can be dramatically increased if it is brought in the form of loosely bound bundles of thin nanowires. The specific heat displays a pronounced double phase transition at 3.7 K and 5.5 K, which we attribute to the inner ‘bulk’ contribution of the nanowires and to the surface contribution, respectively. The latter is visible only because of the large volume fraction of the surface layer in relation to the bulk volume. The upper transition coincides with the onset of the resistive transition, while zero resistance is gradually approached below the lower transition. In contrast to the low critical field H c = 0.03 T of Sn in its bulk form, a magnetic field of more than 3 T is required to fully restore the normal state.