Efficient ab initio Migdal-Eliashberg calculation considering the retardation effect in phonon-mediated superconductors
Efficient ab initio Migdal-Eliashberg calculation considering the retardation effect in phonon-mediated superconductors
复制标题
考虑声子介导超导体中的延迟效应的高效从头算 Migdal-Eliashberg 计算
DOI：
10.1103/physrevb.102.134503
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发表时间：
2020
影响因子：
3.7
通讯作者：
and Ryotaro Arita
中科院分区：
文献类型：
--
作者：
Tianchun Wang;Takuya Nomoto;Yusuke Nomura;Hiroshi Shinaoka;Junya Otsuki;T. Koretsune;and Ryotaro Arita
我们制定了一个有效的计划进行Migdal-Eliashberg计算考虑延迟效应的第一性原理。虽然传统的方法需要大量的松原频率，我们表明，中间表示的绿色的功能[H。Shinaoka，Phys. Rev. B 96，035147（2017）10.1103/PhysRevB.96.035147]显著降低了求解线性化间隙方程的数值成本。在不引入任何经验参数的情况下，得到了与实验一致的Nb（K）超导转变温度。目前的结果表明，我们的方法对许多低于K的超导体具有上级性能。
We formulate an efficient scheme to perform a Migdal-Eliashberg calculation considering the retardation effect from first principles. While the conventional approach requires a huge number of Matsubara frequencies, we show that the intermediate representation of the Green's function [H. Shinaoka , Phys. Rev. B 96, 035147 (2017)10.1103/PhysRevB.96.035147] dramatically reduces the numerical cost to solve the linearized gap equation. Without introducing any empirical parameter, we obtain a superconducting transition temperature of elemental Nb (K), which is consistent with experiment. The present result indicates that our approach has a superior performance for many superconductors for whichis lower thanK.