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arXiv · 1501.06958

Multicomponent fractional quantum Hall states with subband and spin degrees of freedom

Yang Liu·S. Hasdemir·J. Shabani·M. Shayegan·L. N. Pfeiffer·K. W. West·K. W. Baldwin
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Abstract

In wide GaAs quantum wells where two electric subbands are occupied we apply a parallel magnetic field or increase the electron density to cause a crossing of the two $N=0$ Landau levels of these subbands and with opposite spins. Near the crossing, the fractional quantum Hall states in the filling factor range $1<ν<3$ exhibit a remarkable sequence of pseudospin polarization transitions resulting from the interplay between the spin and subband degrees of freedom. The field positions of the transitions yield a new and quantitative measure of the composite Fermions' discrete energy level separations. Surprisingly, the separations are smaller when the electrons have higher spin-polarization.

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Yang Liu, S. Hasdemir, J. Shabani, M. Shayegan, L. N. Pfeiffer, K. W. West, K. W. Baldwin. 2015-11-03. Multicomponent fractional quantum Hall states with subband and spin degrees of freedom. https://doi.org/10.1103/physrevb.92.201101

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