Electrophysical Properties of ZnAs 2 and CdAs 2 at Hydrostatic Pressure up to 9 GPa

Specific electroresistance and Hall coefficient on oriented ZnAs 2 and CdAs 2 single crystals in the region of room temperatures at hydrostatic pressure up to 9 GPa were measured. In p -ZnAs 2 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 -ZnAs 2 samples was not observed, in all probability it occurs under the pressure P >10 GPa. Two groups of n -CdAs 2 samples oriented on 1 0 0] and 0 0 1] directions were investigated. The reversible structural phase transition was observed in investigated n -CdAs 2 samples at P =5.5 GPa from the dependencies of specific electroresistance 𝜌 ( 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 -CdAs 2 . Maxima that earlier weren't observed, were detected on dependencies 𝜌 ( P ), R H ( P ) at P =1.8 GPa and at P =3 GPa.