ELECTRIC-FIELD-INDUCED LOCALIZATION IN ONE-BAND CONDUCTORS

The nonperturbative nonstationary response of a crystalline conductor to an external space-homogeneous electric field of arbitrary magnitude and arbitrary time dependence is considered. The independent-electron one-band approach in arbitrary dimension with dispersion and lattice structure of general type is used in the absence of relaxation process es. A classification of oscillatory localized states induced by time-p eriodic electric fields is put forward. The governing parameters are t he magnitude of the constant component of the field and the period of its oscillating part. In the periodic regime the electron is typically delocalized with a particular localized exception. In the commensurat e case the electron may be delocalized only due to long-range transfer to distant neighbours with an analogous localized exception. And, las t, in the incommensurate regime the electron is always localized. Part icular examples are considered. (C) 1997 Elsevier Science B.V.