Magneto-roton excitation of fractional quantum Hall effect: Comparison between theory and experiment
نویسندگان
چکیده
A major obstacle toward a quantitative verification, by comparison to experiment, of the theory of the excitations of the fractional quantum Hall effect has been the lack of a proper understanding of disorder. We circumvent this problem by studying the neutral magneto-roton excitations, whose energy is expected to be largely insensitive to disorder. The calculated energies of the roton at 1/3, 2/5 and 3/7 fillings of the lowest Landau level are in good agreement with those measured experimentally.
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