SPIN POLARONS AND VARIABLE-RANGE-HOPPING IN MAGNETICALLY DISORDERED-SYSTEMS

Magnetic polarons in magnetically disordered systems (for brevity, spi n-glass polarons) are in one respect very unlike other polarons: Usual polaron hopping at low T proceeds via tunneling, and these polarons d o not affect the T dependence of the hopping rate, while the spin-glas s polaron tunneling is suppressed by the disorder, and their hopping p roceeds via activation for all T. It gives rise to the reentrance of t he simple activated T dependence of variable range hopping conductivit y at very low T. Recent experiments in CdMnTe are discussed.