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

• 作者: Cong Ren Gen-Fu Chen Hai Zi Lei Shan Ling-Xiao Zhao Xing-Yuan Hou Zhian Ren
• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2020,（9）
• 所属期刊栏目: CONDENSED MATTER:ELECTRONIC STRUCTURE,ELECTRICAL,MAGNETIC,AND OPTICAL PROPERTIES
• 页码范围: 84-88
• 页数: 5页
• 语种: 英文
• DOI: 10.1088/0256-307X/37/9/097403

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/kBTc 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 point-contact spectroscopy,offering rich information about high-pressure superconductivity.