Pressure-Dependent Point-Contact Spectroscopy of Superconducting PbTaSe2 Single Crystals  

作　　者：Hai Zi Ling-Xiao Zhao Xing-Yuan Hou Lei Shan Zhian Ren Gen-Fu Chen Cong Ren 子海;赵凌霄;侯兴元;单磊;任治安;陈根富;任聪(School of Physics and Astronomy,Yunnan University,Kunming 650500,China;Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Science,Beijing 100190,China)

机构地区：[1]School of Physics and Astronomy,Yunnan University,Kunming 650500,China [2]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Science,Beijing 100190,China

出　　处：《Chinese Physics Letters》2020年第9期84-88,共5页中国物理快报（英文版）

基　　金：Supported by the National Science Foundation of China(Grant Nos.11574373 and 11774303);the Joint Fund of Yunnan Provincial Science and Technology Department(Grant No.2019FY003008)。

摘　　要：We develop an experimental tool to investigate the order parameter of superconductors by combining pointcontact spectroscopy measurement with high-pressure technique.It is demonstrated for the first time that planar point-contact spectroscopy measurement on noncentrosymmetric superconducting PbTaSe2 single crystals is systematically subjected to hydrostatic pressures up to 12.1 kbar.Under such a high pressure,the normal-state contact resistance is sensitive to the applied pressure,reflecting the underlying variation of contact transparency upon pressures.In a superconducting state,the pressure dependence of the energy gap△0 and the critical temperature Tc for gap opening/closing are extracted based on a generalized Blond-Tinkham-Klapwijk model.The gap ratio 2△0/kB Tc indicates a crossover from weak coupling to strong coupling in electron pairing strength upon pressure for PbTaSe2.Our experimental results show the accessibility and validity of high-pressure pointcontact spectroscopy,offering rich information about high-pressure superconductivity.

关 键 词：technique. COUPLING TRANSPARENCY 

分 类 号：O469[理学—凝聚态物理]