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arXiv · 1011.2022

Observation of exchange Coulomb interactions in the quantum Hall state at nu=3

A. B. Van'kov·T. D. Rhone·A. Pinczuk·I. V. Kukushkin·L. N. Pfeiffer·K. W. West
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Abstract

Coulomb exchange interactions of electrons in the nu=3 quantum Hall state are determined from two inter-Landau level spin-flip excitations measured by resonant inelastic light scattering. The two coupled collective excitations are linked to inter-Landau level spin-flip transitions arising from the N=0 and N=1 Landau levels. The strong repulsion between the two spin-flip modes in the long-wave limit is clearly manifested in spectra displaying Coulomb exchange contributions that are comparable to the exchange energy for the quantum Hall state at nu=1. Theoretical calculations within the Hartree-Fock approximation are in a good agreement with measured energies of spin-flip collective excitations.

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A. B. Van'kov, T. D. Rhone, A. Pinczuk, I. V. Kukushkin, L. N. Pfeiffer, K. W. West. 2010-11-09. Observation of exchange Coulomb interactions in the quantum Hall state at nu=3. https://doi.org/10.1103/physrevb.83.245325

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