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arXiv · 0905.3200

Gate induced g-factor control and dimensional transition for donors in multi-valley semiconductors

Rajib Rahman·Seung H. Park·Timothy B. Boykin·Gerhard Klimeck·Sven Rogge·Lloyd C. L. Hollenberg
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Abstract

The dependence of the g-factors of semiconductor donors on applied electric and magnetic fields is of immense importance in spin based quantum computation and in semiconductor spintronics. The donor g-factor Stark shift is sensitive to the orientation of the electric and magnetic fields and strongly influenced by the band-structure and spin-orbit interactions of the host. Using a multimillion atom tight-binding framework the spin-orbit Stark parameters are computed for donors in multi-valley semiconductors, silicon and germanium. Comparison with limited experimental data shows good agreement for a donor in silicon. Results for gate induced transition from 3D to 2D wave function confinement show that the corresponding g-factor shift in Si is experimentally observable.

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Rajib Rahman, Seung H. Park, Timothy B. Boykin, Gerhard Klimeck, Sven Rogge, Lloyd C. L. Hollenberg. 2009-05-19. Gate induced g-factor control and dimensional transition for donors in multi-valley semiconductors. https://doi.org/10.1103/physrevb.80.155301

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