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arXiv · 1107.5644

Temperature insensitive optical alignment of the exciton in nanowire embedded GaN Quantum Dots

A. Balocchi·J. Renard·C. T. Nguyen·B. Gayral·T. Amand·H. Mariette·B. Daudin·G. Tourbot·X. Marie
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Abstract

We report on the exciton spin dynamics of nanowire embedded GaN/AlN Quantum Dots (QDs) investigated by time-resolved photoluminescence spectroscopy. Under a linearly polarized quasiresonant excitation we evidence the quenching of the exciton spin relaxation and a temperature insensitive degree of the exciton linear polarization, demonstrating the robustness of the optical alignment of the exciton spin in these nanowire embedded QDs. A detailed examination of the luminescence polarization angular dependence shows orthogonal linear exciton eigenstates with no preferential crystallographic orientation.

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A. Balocchi, J. Renard, C. T. Nguyen, B. Gayral, T. Amand, H. Mariette, B. Daudin, G. Tourbot, X. Marie. 2011-07-28. Temperature insensitive optical alignment of the exciton in nanowire embedded GaN Quantum Dots. https://doi.org/10.1103/physrevb.84.235310

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