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Green's function of the half-filled Landau level Chern-Simons theory in the temporal gauge

J. Dietel
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Abstract

We study the Green's function of the $ ν=1/2 $ Chern-Simons system in the temporal (Weyl) gauge. We derive the Chern-Simons path integral in the temporal gauge. In order to do this, we gauge transform the path integral in the Coulomb gauge which represents the partition function of the correct normal ordered Chern-Simons Hamiltonian. We calculate the self energy of this path integral in the random-phase approximation (RPA) for temperature $T=0 $. This self energy does not have the divergence with the logarithm of the area, which is known to imply the vanishing of the exact Green's function in the Coulomb gauge for an infinite area. By Chern-Simons retransforming the path integral representing the Green's function in the temporal gauge we calculate explicitly the exact Green's function under the neglection of the interaction between the electrons, getting a finite value. Furthermore, we give arguments that the Green's function of the interacting system is also finite. The non-vanishing of the Green's function for infinite area is due to a dynamical creation of the phase factors linking the created and annihilated particles with the particles in the ground state. The absence of these phase factors is the reason for the vanishing of the Green's function in the Coulomb gauge.

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J. Dietel. 2003-01-10. Green's function of the half-filled Landau level Chern-Simons theory in the temporal gauge. https://doi.org/10.1103/physrevb.66.195323

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