Superconductivity at 50 K in a mixed-phase Ca–P–O compound system treated by shock-wave pressure up to 65 GPa

Shock-wave pressure treatment up to 65 GPa has been applied to samples representing powdered mixtures of calcium and calcium phosphate in 1:1 volume ratio. Magnetometric measurements have revealed superconductivity of the samples at 50 K. By means of X-ray powder diffraction and magnetometric measurements, it has been found that superconductivity observed in the samples corresponds to instability at ambient pressure and room temperature of the phase/s formed in the samples during their shock-wave pressure treatment.