Metastable:
If we can understand the structure and the mechanics of how high pressures might create a Cooper-pair interaction, we may be able to start doing it at lower pressure. One hope is that the material is “metastable” and won’t fall apart when the pressure is released. Diamond is an example of a metastable material: it is created when carbon atoms are subjected to extremely high pressures, but once it has formed you can remove the pressure and it doesn’t revert to its previous form. [“The superconductor breakthrough that could mean an energy revolution,” Michael Brooks, NewScientist (16 January 2021)]