Band geometry induced electro-optic effect and polarization rotation

TL;DR

This paper explores how band geometry influences the electro-optic effect in materials, emphasizing the roles of Fermi surface, disorder, and quantum metric, with implications for designing advanced photonic modulators.

Contribution

It introduces a comprehensive analysis of band geometry-induced electro-optic effects, highlighting the significance of quantum metric and disorder contributions in $ ext{PT}$ symmetric systems.

Findings

Band geometry significantly affects electro-optic modulation.

Quantum metric plays a crucial role in $ ext{PT}$ symmetric systems.

Electro-optic effect can probe band geometric properties.

Abstract

Electric field-induced modulation of the optical properties is crucial for amplitude and phase modulators used in photonic devices. Here, we present a comprehensive study of the band geometry-induced electro-optic effect, specifically focusing on the Fermi surface and disorder-induced contributions. These contributions are crucial for metallic and semimetallic systems and for optical frequencies comparable to or smaller than the scattering rates. We highlight the importance of the quantum metric and metric connection in generating the electro-optic effect in parity-time reversal ($\mathcal{PT}$) symmetric systems such as CuMnAs. Our findings establish the electro-optic effect as a novel tool to probe band geometric effects and open new avenues to design electrically controlled efficient amplitude and phase modulators for photonic applications.