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arXiv · 1109.1764

Measurement of g-factor tensor in a quantum dot and disentanglement of exciton spins

B. J. Witek·R. W. Heeres·U. Perinetti·E. P. A. M. Bakkers·L. P. Kouwenhoven·V. Zwiller
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Abstract

We perform polarization-resolved magneto-optical measurements on single InAsP quantum dots embedded in an InP nanowire. In order to determine all elements of the electron and hole $g$-factor tensors, we measure in magnetic field with different orientations. The results of these measurements are in good agreement with a model based on exchange terms and Zeeman interaction. In our experiment, polarization analysis delivers a powerful tool that not only significantly increases the precision of the measurements, but also enables us to probe the exciton spin state evolution in magnetic fields. We propose a disentangling scheme of heavy-hole exciton spins enabling a measurement of the electron spin $T_2$ time.

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B. J. Witek, R. W. Heeres, U. Perinetti, E. P. A. M. Bakkers, L. P. Kouwenhoven, V. Zwiller. 2011-12-04. Measurement of g-factor tensor in a quantum dot and disentanglement of exciton spins. https://doi.org/10.1103/physrevb.84.195305

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