Impurity-induced defect states in Pb1-xGexTe alloys doped with gallium

Galvanomagnetic properties of n-Pb1-xGexTe<Ga>(0.04 less than or equal to x less than or equal to 0.08) single crystals have been investigated in the shielded from external background illumination chamber and under controlled illumination from infrared heat source. Low temperature activation range of the impurity conductivity on the dark curves of rho(1/T) was revealed and attributed to the appearance of gallium-induced deep level E-Ga in the gap of the alloys. It was shown that the alloys possess high infrared photosensitivity at temperatures below T-c=50 divided by 60 K, and effect of the persistent photoconductivity at helium temperatures was revealed.