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arXiv · 1007.2404

Electrostatically defined Quantum Dots in a Si/SiGe Heterostructure

A. Wild·J. Sailer·J. Nützel·G. Abstreiter·S. Ludwig·D. Bougeard
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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.

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A. Wild, J. Sailer, J. Nützel, G. Abstreiter, S. Ludwig, D. Bougeard. 2010-07-14. Electrostatically defined Quantum Dots in a Si/SiGe Heterostructure. https://doi.org/10.1088/1367-2630%2F12%2F11%2F113019

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