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Diagrammatic analysis of the two-state quantum Hall system with chiral invariance

S. Hikami·K. Minakuchi
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Abstract

The quantum Hall system in the lowest Landau level with Zeeman term is studied by a two-state model, which has a chiral invariance. Using a diagrammatic analysis, we examine this two-state model with random impurity scattering, and find the exact value of the conductivity at the Zeeman energy $E = Δ$. We further study the conductivity at the another extended state $E = E_1$ ($ E_1 > Δ$). We find that the values of the conductivities at $E = 0$ and $E = E_1$ do not depend upon the value of the Zeeman energy $Δ$. We discuss also the case where the Zeeman energy $Δ$ becomes a random field.

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S. Hikami, K. Minakuchi. 1996-11-13. Diagrammatic analysis of the two-state quantum Hall system with chiral invariance. https://doi.org/10.1103/physrevb.55.7155

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