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Signatures of spin in the n=1/3 Fractional Quantum Hall Effect

A. F. Dethlefsen·E. Mariani·H. -P. Tranitz·W. Wegscheider·R. J. Haug
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Abstract

The activation gap Delta of the fractional quantum Hall state at constant filling n =1/3 is measured in wide range of perpendicular magnetic field B. Despite the full spin polarization of the incompressible ground state, we observe a sharp crossover between a low-field linear dependence of Delta on B associated to spin texture excitations and a Coulomb-like behavior at large B. From the global gap-reduction we get information about the mobility edges in the fractional quantum Hall regime.

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A. F. Dethlefsen, E. Mariani, H. -P. Tranitz, W. Wegscheider, R. J. Haug. 2005-08-17. Signatures of spin in the n=1/3 Fractional Quantum Hall Effect. https://doi.org/10.1103/physrevb.74.165325

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