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arXiv · 2610.16462

Photon echo from Maki-Thompson interference in a fluctuating s-wave superconductor

Hui Zhou·Yuan Wan
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Abstract

We study theoretically the nonlinear optical response of a fluctuating s-wave superconductor driven by two successive terahertz pulses. We show that the response exhibits a photon echo signal that arises from the quantum interference between the time-reversed electron and hole trajectories in the Maki-Thompson process. By contrast, the transport of the fluctuating Cooper pairs responsible for the Aslamazov-Larkin conductivity does not generate an echo. The photon echo signal can be readily measured using terahertz two-dimensional coherent spectroscopy, highlighting its potential to distinguish different fluctuation conductivity mechanisms.

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Hui Zhou, Yuan Wan. 2026-10-12. Photon echo from Maki-Thompson interference in a fluctuating s-wave superconductor. https://arxiv.org/abs/2610.16462

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