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Measurements of the Composite Fermion masses from the spin polarization of 2-D electrons in the region $1<ν<2$

R. Chughtai·V. Zhitomirsky·R. J. Nicholas·M. Henini
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Abstract

Measurements of the reflectivity of a 2-D electron gas are used to deduce the polarization of the Composite Fermion hole system formed for Landau level occupancies in the regime 1<ν<2. The measurements are consistent with the formation of a mixed spin CF system and allow the density of states or `polarization' effective mass of the CF holes to be determined. The mass values at ν=3/2 are found to be ~1.9m_{e} for electron densities of 4.4 x 10^{11} cm^{-2}, which is significantly larger than those found from measurements of the energy gaps at finite values of effective magnetic field.

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R. Chughtai, V. Zhitomirsky, R. J. Nicholas, M. Henini. 2001-11-26. Measurements of the Composite Fermion masses from the spin polarization of 2-D electrons in the region $1<ν<2$. https://doi.org/10.1103/physrevb.65.161305

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