Pressure-induced semiconductor-metal transitions in amorphous InSb

Pressure-induced semiconductor-metal transitions, accompanied by a discontinuous decrease in the resistivity by a factor of 10−4, have been found at room temperature for amorphous InSb under pressures of 10 to 13 kbar. These transitions occur through a series of intermediate structural modifications which remain predominantly in the amorphous state, while the final stage partially transforms into a metastable crystal with a NaCl-type structure. The transformation to the NaCl type is irreversible on releasing the pressure. This material can be classed as a hard superconductor with a transition temperature Tc = 3·4±0·2 K and a critical magnetic field Hc = 9-10 kG.