TRANSPORT-PROPERTIES OF SNTE-MNTE SYSTEM - ANOMALOUS HALL-EFFECT

Electrical measurements have been made of the Bridgman-grown degenerate magnetic semiconductors Sn1−xMnxTe (x<19 at. %) over a temperature range from 300 to 2 K. The magnetic impurities, Mn ions, have an effect on carrier transport in two different ways. First, they act simply as ionized impurity scattering centers giving rise to a decrease in the Hall mobility; the exponent n in the temperature dependence of the Hall mobility in the range 77-300 K, μ∝T−n, and the residual resistivity at 4.2 K, ρ4.2, are affected appreciably by the magnetic impurity concentration. Second, the localized spins on the Mn ions come into play at low temperatures, which align ferromagnetically at an ordering temperature. As a result, the Hall effect consists of the ordinary component due to the Lorentz force and the anomalous one arising from spin dependent scattering of conduction carriers through a spin-orbit coupling; the second component is found to be strongly temperature-dependent, R1∝T2, in agreement with the Yoloshinskii model. © 1979, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.