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Unpaired and spin-singlet paired states of a two-dimensional electron gas in a perpendicular magnetic field

M. Polini·K. Moulopoulos·B. Davoudi·M. P. Tosi
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Abstract

We present a variational study of both unpaired and spin-singlet paired states induced in a two-dimensional electron gas at low density by a perpendicular magnetic field. It is based on an improved circular-cell approximation which leads to a number of closed analytical results. The ground-state energy of the Wigner crystal containing a single electron per cell in the lowest Landau level is obtained as a function of the filling factor $ν$: the results are in good agreement with those of earlier approaches and predict $ν_{c} \approx 0.25$ for the upper filling factor at which the solid-liquid transition occurs. A novel localized state of spin-singlet electron pairs is examined and found to be a competitor of the unpaired state for filling factor $ν>1$. The corresponding phase boundary is quantitatively displayed in the magnetic field-electron density plane.

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M. Polini, K. Moulopoulos, B. Davoudi, M. P. Tosi. 2002-01-26. Unpaired and spin-singlet paired states of a two-dimensional electron gas in a perpendicular magnetic field. https://doi.org/10.1103/physrevb.65.165306

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