Electrical manipulation of an electronic two-state system in Ge/Si quantum dots

C. E. Pryor; M. E. Flatté; J. Levy

doi:10.1063/1.3266864

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arXiv · 0909.4357

Electrical manipulation of an electronic two-state system in Ge/Si quantum dots

C. E. Pryor·M. E. Flatté·J. Levy

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Abstract

We calculate that the electron states of strained self-assembled Ge/Si quantum dots provide a convenient two-state system for electrical control. An electronic state localized at the apex of the quantum dot is nearly degenerate with a state localized at the base of the quantum dot. Small electric fields shift the electronic ground state from apex-localized to base-localized, which permits sensitive tuning of the electronic, optical and magnetic properties of the dot. As one example, we describe how spin-spin coupling between two Ge/Si dots can be controlled very sensitively by shifting the individual dot's electronic ground state between apex and base.

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C. E. Pryor, M. E. Flatté, J. Levy. 2009-09-24. Electrical manipulation of an electronic two-state system in Ge/Si quantum dots. https://doi.org/10.1063/1.3266864

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