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arXiv · 1305.0488

Disorder-induced valley-orbit hybrid states in Si quantum dots

John King Gamble·M. A. Eriksson·S. N. Coppersmith·Mark Friesen
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Abstract

Quantum dots in silicon are promising candidates for implementation of solid-state quantum information processing. It is important to understand the effects of the multiple conduction band valleys of silicon on the properties of these devices. Here we introduce a novel, systematic effective mass theory of valley-orbit coupling in disordered silicon systems. This theory reveals valley-orbit hybridization effects that are detrimental for storing quantum information in the valley degree of freedom, including non-vanishing dipole matrix elements between valley states and altered intervalley tunneling.

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John King Gamble, M. A. Eriksson, S. N. Coppersmith, Mark Friesen. 2013-05-02. Disorder-induced valley-orbit hybrid states in Si quantum dots. https://doi.org/10.1103/physrevb.88.035310

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