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arXiv · 0901.2283

Voltage controlled nuclear polarization switching in a single InGaAs quantum dot

M. N. Makhonin·J. Skiba-Szymanska·M. S. Skolnick·H. -Y. Liu·M. Hopkinson·A. I. Tartakovskii
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Abstract

Sharp threshold-like transitions between two stable nuclear spin polarizations are observed in optically pumped individual InGaAs self-assembled quantum dots embedded in a Schottky diode when the bias applied to the diode is tuned. The abrupt transitions lead to the switching of the Overhauser field in the dot by up to 3 Tesla. The bias-dependent photoluminescence measurements reveal the importance of the electron-tunneling-assisted nuclear spin pumping. We also find evidence for the resonant LO-phonon-mediated electron co-tunneling, the effect controlled by the applied bias and leading to the reduction of the nuclear spin pumping rate.

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M. N. Makhonin, J. Skiba-Szymanska, M. S. Skolnick, H. -Y. Liu, M. Hopkinson, A. I. Tartakovskii. 2009-01-15. Voltage controlled nuclear polarization switching in a single InGaAs quantum dot. https://doi.org/10.1103/physrevb.79.125318

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