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

Article

关键词: CHARGE-DENSITY-WAVE;    HIGH LANDAU-LEVELS;    WIGNER CRYSTAL;    GROUND-STATE;    TRANSLATIONAL SYMMETRY;    FUNCTIONAL THEORY;    INSULATING PHASE;    SOLID TRANSITION;    LAUGHLIN-LIQUID;    QUANTUM LIMIT;   

DOI  :  10.1103/PhysRevB.65.165306

来源: SCIE

【 摘 要 】

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 nu: the results are in good agreement with those of earlier approaches and predict nu(c)approximate to0.25 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 nu>1. The corresponding phase boundary is quantitatively displayed in the magnetic field-electron density plane.

【 授权许可】

Free