Electrophysical properties of ZnAs2 and CdAs2 at hydrostatic pressure up to 9 GPa

Specific electroresistance and Hall coefficient on oriented ZnAs2 and CdAs2 single crystals in the region of room temperatures at hydrostatic pressure up to 9 GPa were measured. In p-ZnAs2 specific electroresistance falls for one order of magnitude with the increase of pressure, and Hall coefficient falls for two orders in magnitude, and at P = 7 GPa specific electroresistance and Hall coefficient come out to a saturation. Under mentioned conditions the phase transition in investigated p-ZnAs2 Samples was not observed, in all probability it occurs under the pressure P > 10 GPa. Two groups of n-CdAs2 samples oriented on [100] and [001] directions were investigated. The reversible structural phase transition was observed in investigated n-CdAs2 samples at P = 5.5 GPa from the dependencies of specific electroresistance p(P) and Hall coefficient R-H(P). On the basis of the values of concentrations and mobilities before and after phase transition a conclusion was made that semiconductor-semiconductor transition takes place in n-CdAs2. Maxima that earlier weren't observed, were detected on dependencies rho(P), R-H(P) at P = 1.8 GPa and at P = 3 GPa.