We propose a mechanism for the observed suppression of the two-dimensional (2D) conducting phase when there is an in-plane magnetic field. We apply our approach, which is based on the memory function formalism, to the spin-polarized electron system. This takes into account both disorder and exchange–correlation effects. We showthat spin polarization significantly favours localization because of the enhancement of the exchange–correlations. A key outcome is that the conducting phase for the fully spin-polarized system is suppressed. The in-plane magnetic field needed to generate the fully spin-polarized state is of the order of 1 T and depends on the carrier density. We determine the metal–insulator phase boundary for the unpolarized and polarized systems, and we estimate the dependence of the critical magnetic field on carrier density.
The effect of spin alignment on the metal-insulator transition in two-dimensional systems
NEILSON, DAVID
2000-01-01
Abstract
We propose a mechanism for the observed suppression of the two-dimensional (2D) conducting phase when there is an in-plane magnetic field. We apply our approach, which is based on the memory function formalism, to the spin-polarized electron system. This takes into account both disorder and exchange–correlation effects. We showthat spin polarization significantly favours localization because of the enhancement of the exchange–correlations. A key outcome is that the conducting phase for the fully spin-polarized system is suppressed. The in-plane magnetic field needed to generate the fully spin-polarized state is of the order of 1 T and depends on the carrier density. We determine the metal–insulator phase boundary for the unpolarized and polarized systems, and we estimate the dependence of the critical magnetic field on carrier density.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.