1302.3986 (Ajit C. Balram et al.)

Magneto-roton screening in the 7/3 fractional quantum Hall effect    [PDF]

Ajit C. Balram, Ying-Hai Wu, G. J. Sreejith, Arkadiusz Wójs, Jainendra K. Jain

In exact diagonalization studies, the excitations of the second Landau level 7/3 fractional Hall state are found to be qualitatively different from their lowest Landau level counterparts at 1/3. We show that the differences arise due to a substantial screening by magneto-rotons, thanks to a relatively small magneto-roton gap and a relatively large residual interaction between composite fermions. This screening produces exceptionally large quasiparticles and quasiholes at 7/3, with diameters in excess of 30 magnetic lengths, which has implications for experiments.

View original: http://arxiv.org/abs/1302.3986