Arrival of the Fermion Superfluid

摘要

All particles are either bosons or fermi-ons. Bosons behave like each other, whereas fermions refuse to act the same. In their lowest energy state, bosons form a Bose-Einstein condensate (BEC) in which all particles behave identically. As a result, quantum phenomena are magnified, becoming observable even at macroscopic length scales. Fermions cannot perform this feat. However, a bound pair of fermions behaves like a boson. A collection of bound fermion pairs should therefore be able to Bose-con-dense as bosons do. Two reports in this issue make a strong case for the realization of such a fermion superfluid in cold atoms.