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arXiv · 1206.1111

Conquer the fine structure splitting of excitons in self-assembled InAs/GaAs quantum dots via combined stresses

Jianping Wang·Ming Gong·Guang-Can Guo·Lixin He
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Abstract

Eliminating the fine structure splitting (FSS) of excitons in self-assembled quantum dots (QDs) is essential to the generation of high quality entangled photon pairs. It has been shown that the FSS has a lower bound under uniaxial stress. In this letter, we show that the FSS of excitons in a general self-assembled InGaAs/GaAs QD can be fully suppressed via combined stresses along the [110] and [010] directions. The result is confirmed by atomic empirical pseudopotential calculations. For all the QDs we studied, the FSS can be tuned to be vanishingly small ($<$ 0.1 $\mu$eV), which is sufficient small for high quality entangled photon emission.

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Jianping Wang, Ming Gong, Guang-Can Guo, Lixin He. 2012-06-06. Conquer the fine structure splitting of excitons in self-assembled InAs/GaAs quantum dots via combined stresses. https://doi.org/10.1063/1.4745188

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