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arXiv · 0801.0571

Optical alignment and polarization conversion of neutral exciton spin in individual InAs/GaAs quantum dots

K. Kowalik·O. Krebs·A. Lemaître·J. A. Gaj·P. Voisin
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Abstract

We investigate exciton spin memory in individual InAs/GaAs self-assembled quantum dots via optical alignment and conversion of exciton polarization in a magnetic field. Quasiresonant phonon-assisted excitation is successfully employed to define the initial spin polarization of neutral excitons. The conservation of the linear polarization generated along the bright exciton eigenaxes of up to 90% and the conversion from circular- to linear polarization of up to 47% both demonstrate a very long spin relaxation time with respect to the radiative lifetime. Results are quantitatively compared with a model of pseudo-spin 1/2 including heavy-to-light hole mixing.

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K. Kowalik, O. Krebs, A. Lemaître, J. A. Gaj, P. Voisin. 2008-01-03. Optical alignment and polarization conversion of neutral exciton spin in individual InAs/GaAs quantum dots. https://doi.org/10.1103/physrevb.77.161305

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