Superconductivity of the FeSe/SrTiO3 Interface in View of BCS–BEC Crossover

作     者：Shuyuan Zhang Guangyao Miao Jiaqi Guan Xiaofeng Xu Bing Liu Fang Yang Weihua Wang Xuetao Zhu Jiandong Guo 张书源;苗光耀;关佳其;徐小凤;刘冰;杨芳;王炜华;朱学涛;郭建东

作者机构：Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190 School of Physical SciencesUniversity of Chinese Academy of SciencesBeijing 100049 Songshan Lake Materials LaboratoryDongguan 523808 Beijing Academy of Quantum Information SciencesBeijing 100193 

出 版 物：《Chinese Physics Letters》 (中国物理快报（英文版）)

年 卷 期：2019年第36卷第10期

页      面：81-85页

核心收录：

学科分类：0502[文学-外国语言文学] 050201[文学-英语语言文学] 05[文学] 

基　　金：Supported by the National Key R&D Program of China under Grant Nos 2017YFA0303600,2016YFA0300600 and2016YFA0202300 the National Natural Science Foundation of China under Grant No 11634016 the Strategic Priority Research Program(B)of Chinese Academy of Sciences under Grant No XDB07030100 the Research Program of Beijing Academy of Quantum Information Sciences under Grant No Y18G09 the Youth Innovation Promotion Association of Chinese Academy of Sciences under Grant No 2016008 the Hundred Talents Program of Chinese Academy of Sciences 

主　　题：crossover BEC regime 

摘      要：In paired Fermi systems,strong many-body effects exhibit in the crossover regime between the Bardeen–Cooper–Schrieffer(BCS)and the Bose–Einstein condensation(BEC)*** concept of the BCS–BEC crossover,which is studied intensively in the research field of cold atoms,has been extended to condensed *** by analyzing the typical superconductors within the BCS–BEC phase diagram,we find that FeSe-based superconductors are prone to shift their positions in the BCS–BEC crossover regime by charge doping or substrate substitution,since their Fermi energies and the superconducting gap sizes are *** at the interface of single-layer FeSe on SrTiO3 substrate,the superconductivity is relocated closer to the crossover unitary than other doped FeSe-based materials,indicating that the pairing interaction is effectively *** further show that hole-doping can drive the interfacial system into the phase with possible pre-paired electrons,demonstrating its flexible tunability within the BCS–BEC crossover regime.