Magnetic Anisotropy Energy in Nickel Arsenide Type Crystals

By the method of melting special powder amounts of cobalt antimonide and cobalt telluride in vacuum, the solid solutions alloys of the CoSb 1–x Te x system were synthesized with the NiAs structure. X-ray analysis results of the alloys confirmed the formation of a continuous series of solid solutions with a nickel-arsenide-type structure in the system. The constants a of the initial CoSb and CoTe compounds are close in values, which determines the course of the dependence a = f(x) that is practically parallel to the concentration axis. The dependence of the constant c on the concentration increases smoothly from 5.181 Å in CoSb to 5.371 Å in CoTe with a slight deflection to the concentration axis. The alloy density, determined by the hydrostatic weighing in carbon tetrachloride, has a linear dependence on the concentration. The concentration dependence of the micro hardness of the CoSb 1–x Te x alloys passes through a weakly expressed maximum in the range of average compositions. Specific magnetization and magnetic susceptibility of the alloys are measured by the ponderomotive method in a magnetic field of 6.8 · 10 5 A/m in the temperature range 80–1200 K. At the temperature of liquid nitrogen, the value of specific magnetization is maximum (~6,0–6,5 Гс · см 3 · г –1 ) in CoTe and solid solutions based on it. Solid solutions of compositions x = 0.4–0.9 have a magnetic transition temperature exceeding 1200 K.