Physicists have watched a quantum fluid do something once thought almost impossible: stop moving. In experiments with ultra-thin graphene, researchers observed a superfluid—normally defined by its ...

Physicists have observed a strange new quantum phase in a graphene-based system, where a superfluid appears to freeze into a solid-like state. Cooling usually pushes matter through a simple sequence.

Conventional ‘vapour-compression’ refrigeration, in which a circulating refrigerant material undergoes gas–liquid phase changes to absorb and expel heat, relies on potent greenhouse gases and consumes ...