Reflection and refraction properties of laser-driven 2D quantum well: Analogy with Photonic Time Crystal

TL;DR

This paper investigates the reflection and refraction of electromagnetic waves in a laser-driven 2D quantum well, revealing its behavior as a photonic time crystal and supporting novel surface wave propagation.

Contribution

It introduces the concept of a laser-driven quantum well acting as a photonic time crystal with unique scattering and surface wave properties, supported by hydrodynamic modeling.

Findings

Quantum well acts as a photonic time crystal with non-shifted and shifted frequency components.

Downshifted satellites can propagate backward and become surface waves under certain conditions.

Supports TE surface wave propagation in s-polarized configuration, which is normally forbidden.

Abstract

It has been demonstrated that a quantum well with optically excited, homogeneous oscillations of a two-dimensional (2D) electron plasma behaves as a photonic time crystal when it scatters an obliquely incident, weak probe electromagnetic wave. The hydrodynamic approximation is used to describe self-consistently the interaction between the probe wave and the 2D plasma. Such a quantum well becomes a polychromatic source and to the first order in perturbation reflected and transmitted radiation reveals as non-shifted in frequency principal components along with up- and down-shifted in frequency satellites. The downshifted satellites are backward propagating when the frequency of the probe wave is less than that of the plasma oscillations. We found the condition when the downshifted components are the surface waves. For the s-polarized probe wave, we found that the laser-driven quantum well can support propagation of TE surface wave, which would not normally be permitted to propagate freely. The amplitudes of the reflected and transmitted components are determined for the principal components and the up- and down-shifted satellites.