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arXiv · 0901.2281

Suppression of nuclear spin diffusion at a GaAs/AlGaAs interface measured with a single quantum dot nano-probe

A. E. Nikolaenko·E. A. Chekhovich·M. N. Makhonin·I. W. Drouzas·A. B. Vankov·J. Skiba-Szymanska·M. S. Skolnick·P. Senellart·A. Lemaitre·A. I. Tartakovskii
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Abstract

Nuclear spin polarization dynamics are measured in optically pumped individual GaAs/AlGaAs interface quantum dots by detecting the time-dependence of the Overhauser shift in photoluminescence (PL) spectra. Long nuclear polarization decay times of ~ 1 minute have been found indicating inefficient nuclear spin diffusion from the GaAs dot into the surrounding AlGaAs matrix in externally applied magnetic field. A spin diffusion coefficient two orders lower than that previously found in bulk GaAs is deduced.

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A. E. Nikolaenko, E. A. Chekhovich, M. N. Makhonin, I. W. Drouzas, A. B. Vankov, J. Skiba-Szymanska, M. S. Skolnick, P. Senellart, A. Lemaitre, A. I. Tartakovskii. 2009-01-15. Suppression of nuclear spin diffusion at a GaAs/AlGaAs interface measured with a single quantum dot nano-probe. https://doi.org/10.1103/physrevb.79.081303

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