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arXiv · 1407.3771

Geometric spin manipulation in semiconductor quantum dots

Sanjay Prabhakar·Roderick Melnik·Akira Inomata
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Abstract

We propose a method to flip the spin completely by an adiabatic transport of quantum dots. We show that it is possible to flip the spin by inducing a geometric phase on the spin state of a quantum dot. We estimate the geometric spin flip time (approximately 2 pico-sec) which turned out to be much shorter than the experimentally reported decoherence time (approx. 100 nano-sec) that would provide an alternative means of fliping the spin before reaching decoherence. It is important that both the Rashba coupling and the Dresselhaus coupling are present for inducing a phase necessary for spin flip. If one of them is absent, the induced phase is trivial and irrelevant for spin-flip.

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Sanjay Prabhakar, Roderick Melnik, Akira Inomata. 2014-07-14. Geometric spin manipulation in semiconductor quantum dots. https://doi.org/10.1063/1.4871004

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