How valley-orbit states in silicon quantum dots probe quantum well interfaces

TL;DR

This paper investigates how valley-orbit states in silicon quantum dots are influenced by interface roughness, confinement, and electron interactions, providing new insights into quantum well interfaces through combined measurements and calculations.

Contribution

It introduces a method to probe quantum well interfaces by measuring and calculating valley-orbit state energies in silicon quantum dots under varying conditions.

Findings

Measured one- and two-electron valley-orbit energies as gate voltages change

Performed full configuration interaction calculations matching experimental data

Provided new understanding of interface effects on valley-orbit states

Abstract

The energies of valley-orbit states in silicon quantum dots are determined by an as yet poorly understood interplay between interface roughness, orbital confinement, and electron interactions. Here, we report measurements of one- and two-electron valley-orbit state energies as the dot potential is modified by changing gate voltages, and we calculate these same energies using full configuration interaction calculations. The results enable an understanding of the interplay between the physical contributions and enable a new probe of the quantum well interface.