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arXiv · 1005.2575

Enhancement of the spin-gap in fully occupied two-dimensional Landau levels

J. Kunc·K. Kowalik·F. J. Teran·P. Plochocka·B. A. Piot·D. K. Maude·M. Potemski·V. Kolkovsky·G. Karczewski·T. Wojtowicz
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Abstract

Polarization-resolved magneto-luminescence, together with simultaneous magneto-transport measurements, have been performed on a two-dimensional electron gas (2DEG) confined in CdTe quantum well in order to determine the spin-splitting of fully occupied electronic Landau levels, as a function of the magnetic field (arbitrary Landau level filling factors) and temperature. The spin splitting, extracted from the energy separation of the σ+ and σ- transitions, is composed of the ordinary Zeeman term and a many-body contribution which is shown to be driven by the spin-polarization of the 2DEG. It is argued that both these contributions result in a simple, rigid shift of Landau level ladders with opposite spins.

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J. Kunc, K. Kowalik, F. J. Teran, P. Plochocka, B. A. Piot, D. K. Maude, M. Potemski, V. Kolkovsky, G. Karczewski, T. Wojtowicz. 2010-05-14. Enhancement of the spin-gap in fully occupied two-dimensional Landau levels. https://doi.org/10.1103/physrevb.82.115438

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