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arXiv · 1311.7106

Enhancement of electron spin lifetime in GaAs crystals: the benefits of dichotomous noise

Stefano Spezia·Dominique Persano Adorno·Nicola Pizzolato·Bernardo Spagnolo
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Abstract

The electron spin relaxation process in n-type GaAs crystals driven by a fluctuating electric field is investigated. Two different sources of fluctuations are considered: (i) a symmetric dichotomous noise and (ii) a Gaussian correlated noise. Monte Carlo numerical simulations show, in both cases, an enhancement of the spin relaxation time by increasing the amplitude of the external noise. Moreover, we find that the electron spin lifetime versus the noise correlation time: (i) increases up to a plateau in the case of dichotomous random fluctuations, and (ii) shows a nonmonotonic behaviour with a maximum in the case of bulks subjected to a Gaussian correlated noise.

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Stefano Spezia, Dominique Persano Adorno, Nicola Pizzolato, Bernardo Spagnolo. 2013-11-28. Enhancement of electron spin lifetime in GaAs crystals: the benefits of dichotomous noise. https://doi.org/10.1209/0295-5075%2F104%2F47011

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