Spin polarization of two-dimensional electrons in different fractional states and around filling factor {nu}=1
- Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, 70569 Stuttgart (Germany)
The spin configuration of the ground state of a two-dimensional electron system is investigated for different fractional quantum Hall effect (FQHE) states from an analysis of circular polarization of time-resolved luminescence. The method clearly distinguishes between fully spin-polarized, partially spin-polarized, and spin-unpolarized FQHE ground states. We demonstrate that FQHE states which are spin unpolarized or partially polarized at low magnetic fields become fully spin polarized at high fields. Temperature dependence of the spin polarization reveals a nonmonotonic behavior at {nu}=(2)/(3). At B{gt}4 T and {nu}{le}1 the electron system is found to be fully spin polarized. This result does not indicate the existence of any Skyrmionic excitations in the high-magnetic-field limit. However, at B{lt}2 T the observed spin depolarization of the electron system at {nu}=(2)/(3) and (4)/(3) becomes broader for lower magnetic fields, so that full spin polarization remains only in a small vicinity around {nu}=1. Such a behavior could be considered as a precursor of Skyrmionic depolarization, which would dominate for smaller ratios between Zeeman and Coulomb energies. {copyright} {ital 1997} {ital The American Physical Society}
- OSTI ID:
- 560723
- Journal Information:
- Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 16 Vol. 55; ISSN 0163-1829; ISSN PRBMDO
- Country of Publication:
- United States
- Language:
- English
Similar Records
Reduction of Spin Polarization near Landau Filling Factor {nu} = 3 in GaAs/AlGaAs Quantum Wells