PRESSURE-INDUCED INSULATOR-METAL TRANSITION IN ELECTRON-IRRADIATED PB1-XSNXSE (X-LESS-THAN-OR-EQUAL-TO-0.03) ALLOYS

Galvanomagnetic effects (B less than or equal to 7T) in electron-irrad iated n- and p-type Pb1-xSnxSe (x less than or equal to 0.03) alloys ( T approximate to 300 K, E=6 Mev, Phi less than or equal to 5.7x10(17) cm(-2)) in the neighborhood of a pressure-induced insulator-metal tran sition (P less than or equal to 18 kbar) are discussed. The field depe ndences of the Hall coefficient calculated in terms of the two-band mo del are in satisfactory agreement with the experimental data, and the main parameters of the charge carriers in irradiated alloys are determ ined. It is shown that there is an increase in the hole concentration in the metallic phase under the action of pressure, associated with th e motion of the energy bands at point L of the Brillouin zone, and tha t electrons overflow from the valence band into the band E-t1 of reson ance states induced by electron irradiation; the parameters of this ba nd are estimated. (C) 1998 American Institute of Physics.