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Path Integral for Composite Fermions in the Half-Filled Lowest Landau Level

W. Weller·J. Dietel·Th. Koschny·W. Apel
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Abstract

We consider electrons in two dimensions in a strong magnetic field at half filling of the lowest Landau level using the Chern-Simons approach. Starting from a lattice Hamiltonian for the electrons, we derive a path integral (PI) formulation for the composite fermions (CF) which respects the order of the operators. We use a time lattice with intermediate times in order to have a PI expressed in density fluctuations. This formulation reveals that there is no infrared (IR) singularity in the grand-canonical potential in lowest order perturbation theory.

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W. Weller, J. Dietel, Th. Koschny, W. Apel. 1998-10-21. Path Integral for Composite Fermions in the Half-Filled Lowest Landau Level. https://arxiv.org/abs/cond-mat/9810273

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