Fabrication and Characterization of Electrostatic Quantum Dots in a Si/SiGe 2D Electron Gas, Including an Integrated Read-out Channel

TL;DR

This paper presents a novel fabrication method for silicon/silicon-germanium quantum dots with integrated read-out channels, enabling stable Coulomb oscillations and advancing spin-based quantum computing in these heterostructures.

Contribution

It introduces a new fabrication technique for quantum dots with integrated read-out channels in Si/SiGe heterostructures, demonstrating stable operation and detection capabilities.

Findings

Reproducible Coulomb oscillations observed

Stable resistance jumps in read-out channel

Progress towards spin-based quantum bits in Si/SiGe

Abstract

A new fabrication technique is used to produce quantum dots with read-out channels in silicon/silicon-germanium two-dimensional electron gases. The technique utilizes Schottky gates, placed on the sides of a shallow etched quantum dot, to control the electronic transport process. An adjacent quantum point contact gate is integrated to the side gates to define a read-out channel and thus allow for noninvasive detection of the electronic occupation of the quantum dot. Reproducible and stable Coulomb oscillations and the corresponding jumps in the read-out channel resistance are observed at low temperatures. The fabricated dot combined with the read-out channel represent a step towards the spin-based quantum bit in Si/SiGe heterostructures.