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Phonon Excitations of Composite Fermion Landau Levels

F. Schulze-Wischeler·F. Hohls·U. Zeitler·D. Reuter·A. D. Wieck·R. J. Haug
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Abstract

Phonon excitations of fractional quantum Hall states at filling factors nu = 1/3, 2/5, 4/7, 3/5, 4/3, and 5/3 are experimentally shown to be based on Landau level transitions of Composite Fermions. At filling factor nu = 2/3, however, a linear field dependence of the excitation energy in the high-field regime rather hints towards a spin transition excited by the phonons. We propose to explain this surprising observation by an only partially polarized 2/3-ground-state making the energetically lower lying spin transition also allowed for phonon excitations.

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F. Schulze-Wischeler, F. Hohls, U. Zeitler, D. Reuter, A. D. Wieck, R. J. Haug. 2004-05-06. Phonon Excitations of Composite Fermion Landau Levels. https://doi.org/10.1142/s0217979204027608

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