JEAN-LOUIS PICHARD

Service de Physique de l'Etat Condense, CEA - Saclay, 91191 Gif sur Yvette Cedex, France

Abstract.

The quantum-classical crossover from the Fermi liquid towards the Wigner solid is numerically revisited using small square lattice models where electrons interact via a Coulomb U/r potential. From exact numerical diagonalizations, one finds that the mesoscopic electron solid is formed in two stages, giving rise to an intriguing solid--liquid regime at intermediate couplings. The roles of a random substrate and of the spin degrees of freedom are investigated. Possible relations with the 2d metal--insulator transition observed in various field effect devices are suggested.

Keywords:  Two-dimensional metal--insulator transition; Wigner crystallization.

Pacs Nos.  71.10-w; 71.27+a; 73.20.Qt