Ferromagnetic vs. Nonmagnetic Phases of 2-D Wigner Electron Crystal

摘要

The ferromagnetic and nonmagnetic phases of 2-D Wigner electron crystal are investigated using a localized representation for the electrons. The ground-state energies of ferromagnetic and nonmagnetic phases of 2-D Wigner electron crystasl are computed in the range of r_s = 10-200. The low density favorable for Wigner crystallization is found to be 2.85 X 10~13 e cm~(-2) for ferromagnetic phase and 5.07 X 10~13 e cm~(-2) for the nonmagnetic phase of 2-D Wigner electron crystal. For the given structure, the ground-state energies of ferromagnetic and nonmagnetic phases are compared. It is found that the energy of the ferromagnetic phase is less than that of the nonmagnetic phase of the 2-D Wigner electron crystal. Also, the results are compared with various experimental and theoretical works and it is found that our results are in good agremeent with the experimental and other theoretical results for the 2-D Wigner electron crystal. The structure-dependent Wannier functions, which give proper localized represeentation for Wigner electrons, are employed in the calculation. The role of correlation energy is suitably taken into account.