Probe and Control of the Reservoir Density of States in Single-Electron Devices

TL;DR

This paper investigates the density of states in electron accumulation layers near Si-SiO2 interfaces using phosphorus donors and quantum dots, providing a new method to identify excited states in nanostructures.

Contribution

It introduces a novel experimental approach to probe and control the density of states in single-electron devices, aligning experimental results with theoretical predictions.

Findings

Peaks in the density of states can be independently shifted in the transport window.

The method allows rapid identification of excited states in nanostructures.

Experimental results agree with theoretical analysis.

Abstract

We present a systematic study of quasi-one-dimensional density of states (DOS) in electron accumulation layers near a Si-SiO2 interface. In the experiments we have employed two conceptually different objects to probe DOS, namely, a phosphorus donor and a quantum dot, both operating in the single-electron tunneling regime. We demonstrate how the peaks in DOS can be moved in the transport window independently of the other device properties, and in agreement with the theoretical analysis. This method introduces a fast and convenient way of identifying excited states in these emerging nanostructures.