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arXiv · 1012.1363

Measurement of valley splitting in high-symmetry Si/SiGe quantum dots

Matthew G. Borselli·Richard S. Ross·Andrey A. Kiselev·Edward T. Croke·Kevin S. Holabird·Peter W. Deelman·Leslie D. Warren·Ivan Alvarado-Rodriguez·Ivan Milosavljevic·Fiona C. Ku·Wah S. Wong·Adele E. Schmitz·Marko Sokolich·Mark F. Gyure·Andrew T. Hunter
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Abstract

We have demonstrated few-electron quantum dots in Si/SiGe and InGaAs, with occupation number controllable from N = 0. These display a high degree of spatial symmetry and identifiable shell structure. Magnetospectroscopy measurements show that two Si-based devices possess a singlet N =2 ground state at low magnetic field and therefore the two-fold valley degeneracy is lifted. The valley splittings in these two devices were 120 and 270 μeV, suggesting the presence of atomically sharp interfaces in our heterostructures.

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Matthew G. Borselli, Richard S. Ross, Andrey A. Kiselev, Edward T. Croke, Kevin S. Holabird, Peter W. Deelman, Leslie D. Warren, Ivan Alvarado-Rodriguez, Ivan Milosavljevic, Fiona C. Ku, Wah S. Wong, Adele E. Schmitz, Marko Sokolich, Mark F. Gyure, Andrew T. Hunter. 2011-04-13. Measurement of valley splitting in high-symmetry Si/SiGe quantum dots. https://doi.org/10.1063/1.3569717

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