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The resistivity ρ, magnetoresistance Δρxx/ρ0(P), and Hall coefficient RH are measured in a (Cd1 ‒ xZnx)3As2 sample with х = 0.31 under the action of uniform pressure and at various temperatures in the range 80–400 K. These samples are obtained by the modified Bridgman method. The composition of the samples and their homogeneity are controlled by X-ray phase analysis and energy-dispersive X-ray spectroscopy. The results of energy dispersive X-ray spectroscopy show that the distribution of elements in the sample is uniform. It is found that the resistivity increases with increasing temperature, and the change in ρ(T) has a metallic character. The Hall coefficient RH in the field decreases slightly with increasing temperature and retains a negative sign throughout the entire range under study. With increasing pressure, anomalies are observed in the baric dependences of the electrical resistivity ρ(Р), magnetoresistance Δρxx/ρ0(Р), and the Hall coefficient RH(Р). Increasing the uniform pressure leads to suppression of the positive magnetoresistance. In the phase-transition region, the negative magnetoresistance at a pressure of Р (2.4–2.7) GPa in a field of 5 kOe is a maximum value of 1.7. [ABSTRACT FROM AUTHOR]

The results of experimental studies of the resistivity, Hall effect, and magnetoresistance of Cd3As2 + kMnAs composites (k = 20, 30, 44.7 mol %) in a toroid-type high-pressure chamber, which makes it possible to create a hydrostatic pressure up to 9 GPa at room temperature in magnetic fields up to 5 kOe, are presented. With increasing pressure, the electrical resistance of samples with different manganese contents is shown to increase at different rates. In the pressure range 4.2–4.4 GPa, a reversible structural transition is observed. An increase in pressure suppresses the positive component of the magnetoresistance; at pressures of P ≈ 1.0 and P ≈ 2.6 GPa, a region of negative magnetoresistance is observed. With a further increase in pressure, the magnetoresistance increases nonmonotonically up to Р ≈ 4.3 GPa, i.e., the phase transition region. [ABSTRACT FROM AUTHOR]