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arXiv · 1112.2585

Highly Non-linear Excitonic Zeeman Spin-Splitting in Composition-Engineered Artificial Atoms

V. Jovanov·T. Eissfeller·S. Kapfinger·E. C. Clark·F. Klotz·M. Bichler·J. G. Keizer·P. M. Koenraad·M. S. Brandt·G. Abstreiter·J. J. Finley
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Abstract

Non-linear Zeeman splitting of neutral excitons is observed in composition engineered In(x)Ga(1-x)As self-assembled quantum dots and its microscopic origin is explained. Eight-band k.p simulations, performed using realistic dot parameters extracted from cross-sectional scanning tunneling microscopy, reveal that a quadratic contribution to the Zeeman energy originates from a spin dependent mixing of heavy and light hole orbital states in the dot. The dilute In-composition (x<0.35) and large lateral size (40-50 nm) of the quantum dots investigated is shown to strongly enhance the non-linear excitonic Zeeman gap, providing a blueprint to enhance such magnetic non-linearities via growth engineering.

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V. Jovanov, T. Eissfeller, S. Kapfinger, E. C. Clark, F. Klotz, M. Bichler, J. G. Keizer, P. M. Koenraad, M. S. Brandt, G. Abstreiter, J. J. Finley. 2011-12-12. Highly Non-linear Excitonic Zeeman Spin-Splitting in Composition-Engineered Artificial Atoms. https://doi.org/10.1103/physrevb.85.165433

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