arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2203.06192cond-mat.supr-concond-mat.mtrl-sci
收藏

超电流诱导共振光学响应

Supercurrent induced resonant optical response

Philip J. D. Crowley, Liang Fu

摘要:

电导率编码了对时间相关电场的电流响应。我们发展了直流超电流存在下的光电导$σ(ω)$理论。电流诱导的光学响应是禁止伽利略不变性发生在系统中的一个单一的抛物线带。然而,我们发现,晶格效应引起了一个明显的电流依赖峰在$σ(ω)$的间隙边缘$ω= 2 Δ$,这发散在清洁的限制。我们证明了这一点在一个多带超导体的模型。我们的理论解释了Nakamura等人(2019)最近在NbN中光学电导率中观察到的电流诱导峰,并为光直接激活Higgs模式提供了一种新的机制。

英文摘要:

The optical conductivity encodes the current response to a time dependent electric field. We develop a theory of the optical conductivity $σ(ω)$ in presence of a dc supercurrent. Current induced optical response is prohibited by Galilean invariance from occurring in systems with a single parabolic band. However, we show that lattice effects give rise to a pronounced current dependent peak in $σ(ω)$ at the gap edge $ω= 2 Δ$, which diverges in the clean limit. We demonstrate this in a model of a multi-band superconductor. Our theory explains the recent observation of a current induced peak in the optical conductivity in NbN by Nakamura et al. (2019), and provides a new mechanism for direct activation of the Higgs mode with light.

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。

↑