Electrostatically defined quantum dots in a Si/SiGe heterostructure
نویسندگان
چکیده
We present an electrostatically defined few-electron double quantum dot (QD) realized in a molecular beam epitaxially 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 to 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. 4 Authors to whom any correspondence should be addressed. New Journal of Physics 12 (2010) 113019 1367-2630/10/113019+16$30.00 © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft
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