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Composite fermions close to the one-half filling of the lowest Landau level revisited

Behnam Farid
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Abstract

By strictly adhering to the microscopic theory of composite fermions (CFs) for the Landau-level filling fractions ν_e = p/(2 p + 1), we reproduce, with remarkable accuracy, the surface-acoustic-wave (SAW)-based experimental results by Willett and co-workers concerning two-dimensional electron systems with ν_e close to 1/2. Our results imply that the electron band mass m_b, as distinct from the CF mass m_*, must undergo a substantial increase under the conditions corresponding to ν_e close to 1/2. We further establish that a finite mean-free path \ell_0 is essential for the observed linearity of the longitudinal conductivity σ_{xx}(q) as deduced from the SAW velocity shifts.

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Behnam Farid. 2000-03-07. Composite fermions close to the one-half filling of the lowest Landau level revisited. https://arxiv.org/abs/cond-mat/0003064

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