Strong-coupling superconductivity with Tc above 70 K in Be-decorated monolayer T-graphene  

作　　者：Liu Yang Peng-Fei Liu Hao-Dong Liu Ya-Ping Li Na Jiao Hong-Yan Lu Bao-Tian Wang Ping Zhang 

机构地区：[1]School of Physics and Physical Engineering,Qufu Normal University,Qufu 273165,China [2]Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China [3]Spallation Neutron Source Science Center,Dongguan 523803,China [4]Institute of Applied Physics and Computational Mathematics,Beijing 100088,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2024年第1期99-105,共7页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.12074213,11574108,12074381,and 12104458);the Major Basic Program of Natural Science Foundation of Shandong Province(Grant No.ZR2021ZD01);the Project of Introduction and Cultivation for Young Innovative Talents in Colleges and Universities of Shandong Province。

摘　　要：Using first-principles calculations,we predict a new type of two-dimensional(2D)beryllium(Be)-decorated T-graphene named BeC_(2),where Be atoms are inserted into C–C bonds linking the carbon tetrarings of T-graphene.The band structure shows that BeC_(2)is metallic,thus,the possible phonon-mediated superconductivity is explored based on the Eliashberg equation.The calculated electron-phonon coupling(EPC)constantλis up to 4.07,and the corresponding superconducting critical temperature(Tc)is 72.1 K,approaching the liquid nitrogen temperature.The reason for the high Tc is the strong EPC.And it is proved to be an anisotropic single-gap superconductor by analyzing the superconducting gap?kof BeC_(2).The electronic susceptibility calculation shows strong nesting effect in BeC_(2).Since rare 2D superconductors show such a strong EPC constantλwhich originates from the coupling between electrons in C-pzorbital and in-plane vibrations of Be and C atoms,the predicted BeC_(2)provides a new platform for investigating strong EPC 2D superconductor.

关 键 词：two-dimensional carbon-based superconductor electron-phonon coupling strong coupling high superconducting critical temperature 

分 类 号：O511[理学—低温物理]