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Anomalous in-plane magneto-optical anisotropy of self-assembled quantum dots

T. Kiessling·A. V. Platonov·G. V. Astakhov·T. Slobodskyy·S. Mahapatra·W. Ossau·G. Schmidt·K. Brunner·L. W. Molenkamp
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Abstract

We report on a complex nontrivial behavior of the optical anisotropy of quantum dots that is induced by a magnetic field in the plane of the sample. We find that the optical axis either rotates in the opposite direction to that of the magnetic field or remains fixed to a given crystalline direction. A theoretical analysis based on the exciton pseudospin Hamiltonian unambiguously demonstrates that these effects are induced by isotropic and anisotropic contributions to the heavy-hole Zeeman term, respectively. The latter is shown to be compensated by a built-in uniaxial anisotropy in a magnetic field B_c = 0.4 T, resulting in an optical response typical for symmetric quantum dots.

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T. Kiessling, A. V. Platonov, G. V. Astakhov, T. Slobodskyy, S. Mahapatra, W. Ossau, G. Schmidt, K. Brunner, L. W. Molenkamp. 2006-01-12. Anomalous in-plane magneto-optical anisotropy of self-assembled quantum dots. https://doi.org/10.1103/physrevb.74.041301

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