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arXiv · 1204.2267

Coherent electrical rotations of valley states in Si quantum dots using the phase of the valley-orbit coupling

Yue Wu·Dimitrie Culcer
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Abstract

A gate electric field has a small but non-negligible effect on the phase of the valley-orbit coupling in Si quantum dots. Finite interdot tunneling between valley eigenstates in a double quantum dot is enabled by a small difference in the phase of the valley-orbit coupling between the two dots, and it in turn allows controllable rotations of two-dot valley eigenstates at a level anticrossing. We present a comprehensive analytical discussion of this process, with estimates for realistic structures.

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Yue Wu, Dimitrie Culcer. 2012-04-10. Coherent electrical rotations of valley states in Si quantum dots using the phase of the valley-orbit coupling. https://doi.org/10.1103/physrevb.86.035321

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