Reconfigurable photoinduced metamaterials in the microwave regime

TL;DR

This paper explores optically reconfigurable dielectric metamaterials at microwave frequencies, demonstrating how photoinduced gratings in semiconductors can dynamically alter their electromagnetic properties.

Contribution

It provides an analytical framework for understanding and predicting the microwave response of photoinduced gratings in semiconductors, highlighting their reconfigurability and anisotropic behavior.

Findings

Metamaterials exhibit high reconfigurability via optical control.

Photogenerated gratings induce anisotropic dielectric responses.

Semiconductor parameters significantly influence microwave behavior.

Abstract

We investigate optically reconfigurable dielectric metamaterials at gigahertz frequencies. More precisely, we study the microwave response of a subwavelength grating optically imprinted into a semiconductor slab. In the homogenized regime, we analytically evaluate the ordinary and extraordinary component of the effective permittivity tensor by taking into account the photo-carrier dynamics described by the ambipolar diffusion equation. We analyze the impact of semiconductor parameters on the gigahertz metamaterial response which turns out to be highly reconfigurable by varying the photogenerated grating and which can show a marked anisotropic behavior.