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Stability of the compressible quantum Hall state around the half-filled Landau level

Kenzo Ishikawa·Nobuki Maeda·Tetsuyuki Ochiai
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Abstract

We study the compressible states in the quantum Hall system using a mean field theory on the von Neumann lattice. In the lowest Landau level, a kinetic energy is generated dynamically from Coulomb interaction. The compressibility of the state is calculated as a function of the filling factor $ν$ and the width $d$ of the spacer between the charge carrier layer and dopants. The compressibility becomes negative below a critical value of $d$ and the state becomes unstable at $ν=1/2$. Within a finite range around $ν=1/2$, the stable compressible state exists above the critical value of $d$.

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Kenzo Ishikawa, Nobuki Maeda, Tetsuyuki Ochiai. 1999-05-25. Stability of the compressible quantum Hall state around the half-filled Landau level. https://doi.org/10.1103/physrevlett.82.4292

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