Supersolid Discoverer’s New Experiments Show No Supersolid

The first evidence of a superfluidlike state in solid helium came from 2004 experiments that, with improvements, now find no supersolidity.

The concept of “supersolid” helium—a bizarre material that does the atomic-scale equivalent of walking through walls—was supported by experiments in dozens of labs starting in 2004. Many doubts have since emerged, and now the researcher whose work kicked off the field reports in Physical Review Letters that all of those early results were misunderstood. His latest version of the apparatus, designed in response to issues raised since 2004, shows no sign of supersolidity. Researchers in the field say, however, that the pursuit of supersolidity has opened up new areas of study, such as research on the effects of quantum states of atoms on macroscopic material properties.