What are the reasons for skepticism?
There are several, Norman says. First, the undoped material, lead apatite, isn’t a metal but rather a nonconducting mineral. And that’s an unpromising starting point for making a superconductor. What’s more, lead and copper atoms have similar electronic structures, so substituting copper atoms for some of the lead atoms shouldn’t greatly affect the electrical properties of the material, Norman says. “You have a rock, and you should still end up with a rock.” On top of that, lead atoms are very heavy, which should suppress the vibrations and make it harder for electrons to pair, Norman explains.