Memory of pressure-induced superconductivity in a phase-change alloy

The application of pressure has been speculated to boost the search for high-temperature superconductors, especially in superhydrides. However, the applied pressure as high as hundreds of GPa needed to create superconductivity in those materials limits their technological application. Finding a route to achieve the high-temperature superconductivity at near-ambient conditions is attractive. By choosing a phase-change alloy ${\mathrm{Ge}}_{2}{\mathrm{Sb}}_{2}{\mathrm{Te}}_{5}$, we study the phase evolution of this material with pressure from the trigonal phase through the amorphous to the body-centered cubic one by the measurements of x-ray diffraction, Raman scattering, resistivity, and Hall coefficient. Superconductivity is observed to take place in the last two phases and can maintain at nearly ambient pressure in the decompression run. Pressure-induced disorder is found to be the key for holding superconductivity in the compressed phase-change alloy.