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Phonon-mediated drag at $ν=1/2$: A test of the Chern-Simons composite fermion theory

Martin C. Bonsager·Yong Baek Kim·A. H. MacDonald
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Abstract

We report on a study of the phonon-mediated frictional drag between two-dimensional electron layers at the Landau level filling factor $ν=1/2$ predicted by Chern-Simons composite-fermion theory. Frictional drag between widely spaced layers is dominated by the phonon-mediated interaction and is altered from its zero-field form because of the large composite-fermion effective mass and, less strongly, by magnetic local-field effects. We find that the reduced drag resistance $ρ(T)/T^2$ peaks at a larger temperature and has a different density dependence than at zero field. We compare these results with recent experimental findings.

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Martin C. Bonsager, Yong Baek Kim, A. H. MacDonald. 2000-03-05. Phonon-mediated drag at $ν=1/2$: A test of the Chern-Simons composite fermion theory. https://doi.org/10.1103/physrevb.62.10940

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