Electrostatically defined Quantum Dots in a Si/SiGe Heterostructure

TL;DR

This paper demonstrates the creation and characterization of a stable, electrostatically defined double quantum dot in Si/SiGe heterostructures, highlighting its potential for quantum computing applications.

Contribution

It introduces a method to realize stable double quantum dots in Si/SiGe heterostructures and analyzes their transport properties and noise resilience.

Findings

Successful fabrication of a double quantum dot in Si/SiGe

Charge noise does not impair device stability

Device shows promise for spin qubit applications

Abstract

We present an electrostatically defined few-electron double quantum dot (QD) realized in a molecular beam epitaxy grown Si/SiGe heterostructure. Transport and charge spectroscopy with an additional QD as well as pulsed-gate measurements are demonstrated. We discuss technological challenges specific for silicon-based heterostructures and the effect of a comparably large effective electron mass on transport properties and tunability of the double QD. Charge noise, which might be intrinsically induced due to strain-engineering is proven not to affect the stable operation of our device as a spin qubit. Our results promise the suitability of electrostatically defined QDs in Si/SiGe heterostructures for quantum information processing.