Structure and Superconductivity of the High-Pressure Phases of InSb

The high-pressure phases of InSb can be retained metastably at 1 atm by cooling to 77°K before releasing pressure. The orthorhombic phase is obtained by applying pressures much higher than the ∼30 kbar needed to obtain the β-Sn phase. X-ray powder patterns of the quenched phases are given. X-ray-diffraction studies at high pressures show that the β-Sn phase is only observed when the pressure is raised rapidly through the 23–30-kbar range. The superconducting transition temperature of the orthorhombic phase is ∼3.4°K which is about 1° higher than that of the β-Sn phase.