Magnetic field suppression of the conducting state in two dimensions

The anomalous conducting phase that has been shown to exist in zero magneti c field in dilute two-dimensional electron systems in silicon is driven int o a strongly insulating state by a magnetic field of about 2 T applied at a ny angle to the 2D plane. Once the conducting phase is quenched, the behavi or of this system in a magnetic held is similar to that of disordered GaAs/ AlGaAs heterostructures. Our results demonstrate that the suppression of th e conducting phase is related only to the electrons' spin. (C) 1998 Publish ed by Elsevier Science B.V. All rights reserved.