Enhanced dielectric response by disordered nanoscale/mesoscopic insulators

TL;DR

This paper proposes a theoretical method to significantly enhance the dielectric response of insulators using disorder-induced quantum interference effects in nanoscale systems, with potential practical material applications.

Contribution

It introduces a novel approach to boost dielectric response through disorder and quantum interference, highlighting topologically protected resonant tunneling effects.

Findings

Dielectric response can be increased by a factor of 30-40 due to disorder.

Resonant tunneling plays a key role in the enhanced response.

Theoretical feasibility of realizing this effect with accessible materials.

Abstract

Enhancement of the dielectric response of insulators by disorder is theoretically proposed, where the quantum interference of electronic waves through the nanoscale/mesoscopic system and its change due to external perturbations control the polarization. In the disordered case with all the states being localized, the resonant tunneling, which is topologically protected, plays a crucial role, and enhances the dielectric response by a factor 30~40 compared with the pure case. Realization of this idea with accessible materials/structures is also discussed.