论文标题
清洁超导膜的非线性微波反应
Nonlinear microwave response of clean superconducting films
论文作者
论文摘要
我们开发了一种明确的规格不变的半经典方法，以研究超导体对单色THZ辐射的非线性响应。我们证明，在干净的超导体中，电荷保守性禁止对均匀场的非线性响应。我们将方法应用于准二维膜，并获得光诱导的电流的明确表达。我们发现，光诱导的电流对辐射的极化角度和入射角表现出强烈的依赖。我们的预测可以直接验证，并在实验中进行了准二维超导膜的实验。
We develop an explicitly gauge-invariant semiclassical approach to investigate nonlinear response of superconductors to monochromatic THz radiation. We demonstrate that in clean superconductors charge conservation forbids non-linear response to a uniform field. We apply our approach to quasi-two-dimensional films and obtain an explicit expression for the photoinduced current. We find that the photoinduced current exhibits a strong dependence on polarization and incidence angle of the radiation. Our predictions may be directly verified in experiments with quasi-two-dimensional superconducting films.
