Abstract
Using first-principles calculations,we predict a new type of two-dimensional(2D)beryllium(Be)-decorated T-graphene named BeC2,where Be atoms are inserted into C-C bonds linking the carbon tetrarings of T-graphene.The band structure shows that BeC2 is metallic,thus,the possible phonon-mediated superconductivity is explored based on the Eliashberg equation.The calcu-lated electron-phonon coupling(EPC)constant λ is 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 △k of BeC2.The electronic susceptibility calcula-tion shows strong nesting effect in BeC2.Since rare 2D superconductors show such a strong EPC constant λ which originates from the coupling between electrons in C-pz orbital and in-plane vibrations of Be and C atoms,the predicted BeC2 provides a new platform for investigating strong EPC 2D superconductor.
基金项目
National Natural Science Foundation of China(12074213)
National Natural Science Foundation of China(11574108)
National Natural Science Foundation of China(12074381)
National Natural Science Foundation of China(12104458)
Major Basic Program of Natural Science Foundation of Shandong Province(ZR2021ZD01)
Project of Introduction and Cultivation for Young Innovative Talents in Colleges and Universities of Shandong Province()
维普
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