arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1008.2822cond-mat.supr-con
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高压下简单金属的Tc图与超导电性

Tc map and superconductivity of simple metals at high pressure

Fan Wei, Y. L. Li, J. L. Wang, L. J. Zou, Z. Zeng

摘要:

我们利用简单声子谱计算了弱电子-声子耦合区的Tc图。利用线性响应方法和密度泛函理论计算了简单金属在压力作用下的声子谱和Eliashberg函数。根据简单金属超导参数在Tc图上随压力的变化,发现简单金属对压力有两种不同的响应:(1)电子-声子相互作用$λ$增强,如La和Li;(2)声子频率增加,如Pb和Pt。发现了$λ$阈值效应,它起源于电子-声子相互作用和电子-电子库仑相互作用的竞争,是大多数简单金属超导体Tc高于0.1K的原因。

英文摘要:

We calculate Tc map in region of weak electron-phonon coupling based on simple phonon spectrum. By using linear-response method and density functional theory, we calculate phonon spectra and Eliashberg functions of simple metals under pressure. Based on the evolutions of superconducting parameters of simple metals on the Tc map with increasing pressure, we find that there are two different responses to pressure for simple metals: (1) enhancing electron-phonon interaction $λ$ such as for La and Li, (2) increasing phonon frequency such as for Pb, Pt. The $λ$ threshold effect is found, which origins from the competition between electron-phonon interaction and electron-electron Coulomb interaction and is the reason why Tc of most superconductors of simple metals are higher than 0.1K.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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