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arXiv · 1310.7819

Quantum limit for nuclear spin polarization in semiconductor quantum dots

Julia Hildmann·Eleftheria Kavousanaki·Guido Burkard·Hugo Ribeiro
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Abstract

A recent experiment [E. A. Chekhovich et al., Phys. Rev. Lett. 104, 066804 (2010)] has demonstrated that high nuclear spin polarization can be achieved in self-assembled quantum dots by exploiting an optically forbidden transition between a heavy hole and a trion state. However, a fully polarized state is not achieved as expected from a classical rate equation. Here, we theoretically investigate this problem with the help of a quantum master equation and we demonstrate that a fully polarized state cannot be achieved due to formation of a nuclear dark state. Moreover, we show that the maximal degree of polarization depends on structural properties of the quantum dot.

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Julia Hildmann, Eleftheria Kavousanaki, Guido Burkard, Hugo Ribeiro. 2013-10-29. Quantum limit for nuclear spin polarization in semiconductor quantum dots. https://doi.org/10.1103/physrevb.89.205302

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