A piece of silver antimony telluride is like a sponge: it readily soaks up heat and turns it into electricity. Such materials are called thermoelectrics, and they already work in space probes and car refrigerators. But if you squeeze this sponge, it starts behaving like a superconductor — current flows with zero resistance.

Already at a pressure of 0.38 GPa (as if a 4-ton weight were placed on every square centimeter), the material loses resistance at 3.2 kelvin — colder than outer space. The stronger the squeeze, the higher the transition temperature: at 31.9 GPa it reaches 6.9 kelvin. And when the pressure was released, superconductivity didn't vanish immediately but even strengthened slightly — up to 7.4 kelvin.

The most surprising part: the crystal lattice remained cubic up to 21.7 GPa, then lost long-range order — atoms stopped lining up in strict rows. But upon releasing pressure, the structure fully recovered, like a spring. This means the material can be squeezed and released many times without damage.

This discovery shows that pressure is a simple and reversible way to switch the properties of thermoelectrics. In the future, such materials could not only convert heat into current but also serve as superconducting elements in electronics or sensors.