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arXiv · 1401.4796

Spin relaxation of a diffusively moving carrier in a random hyperfine field

R. C. Roundy·M. E. Raikh
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Abstract

Relaxation, , of the average spin of a carrier in course of hops over sites hosting random hyperfine fields is studied theoretically. In low dimensions, d = 1, 2, the decay of average spin with time is non-exponential at all times. The origin of the effect is that for d = 1, 2 a typical random-walk trajectory exhibits numerous self-intersections. Multiple visits of the carrier to the same site accelerates the relaxation since the corresponding partial rotations of spin during these visits add up. Another consequence of self-intersections of the random-walk trajectories is that, in all dimensions, the average, , becomes sensitive to a weak magnetic field directed along z. Our analytical predictions are complemented by the numerical simulations of .

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R. C. Roundy, M. E. Raikh. 2014-01-20. Spin relaxation of a diffusively moving carrier in a random hyperfine field. https://doi.org/10.1103/physrevb.90.201203

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