Light-driven interlayer propagation of collective-mode excitations in layered superconductors

Niklas Ziereis; Kazuaki Takasan; Naoto Tsuji

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arXiv · 2403.08734

Light-driven interlayer propagation of collective-mode excitations in layered superconductors

Niklas Ziereis·Kazuaki Takasan·Naoto Tsuji

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Abstract

Superconductors exhibit a nonlinear interaction with an applied light, which can resonantly excite the collective amplitude (Higgs) mode. Here we study light-induced dynamics of layered superconductors, where each layer is coupled to adjacent layers via the Josephson coupling and the first few layers near the surface are driven by an in-plane-polarized light. We study the system under the assumption that the interlayer Coulomb interactions are sufficiently screened out and that the phase-difference mode becomes available in the low-energy regime. We find that interlayer transport is induced via excitations of the collective amplitude and phase-difference modes, even when the applied electric field is parallel to the planes. We provide analytic calculations as well as numerical simulations of the real-time dynamics, and investigate the influence on the light-induced interlayer Josephson current and intralayer third-harmonic generation.

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Niklas Ziereis, Kazuaki Takasan, Naoto Tsuji. 2024-03-13. Light-driven interlayer propagation of collective-mode excitations in layered superconductors. https://arxiv.org/abs/2403.08734

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