Effects of the interfacial polarization on tunneling in surface coupled quantum dots

TL;DR

This paper models the influence of interfacial polarization on carrier tunneling in quantum dots near interfaces, revealing how electrode polarizability can significantly alter tunneling rates, especially for heavier carriers.

Contribution

It introduces an exact polarization model integrated into the Schrödinger equation to analyze tunneling in quantum dot heterostructures, highlighting the impact of dielectric properties.

Findings

Polarization can significantly increase tunneling rates for heavier carriers.

The method can be extended to exciton dissociation and Coulomb blockade calculations.

Volume states can undergo substantial tunneling modifications due to polarization effects.

Abstract

Polarization effects are included exactly in a model for a quantum dot in close proximity to a planar interface. Efficient incorporation of this potential into the Schr\"{o}dinger equation is utilized to map out the influence of the image potential effects on carrier tunneling in such heterostructures. In particular, the interplay between carrier mass and the dielectric constants of a quantum dot, its surrounding matrix, and the electrode is studied. We find that the polarizability of the planar electrode structure can significantly increase the tunneling rates for heavier carriers, potentially resulting in a qualitative change in the dependence of tunneling rate on mass. Our method for treating polarization can be generalized to the screening of two particle interactions, and can thus be applied to calculations such as exciton dissociation and the Coulomb blockade. In contrast to tunneling via intermediate surface localized states of the quantum dot, our work identifies the parameter space over which volume states undergo significant modification in their tunneling characteristics.