Emergence of a molecular Bose–Einstein condensate from a Fermi gas

摘要: The realization of superfluidity in a dilute gas fermionic atoms, analogous to superconductivity metals, represents long-standing goal ultracold research. In such superfluid, it should be possible adjust the interaction strength and tune system continuously between two limits: Bardeen–Cooper–Schrieffer (BCS)-type superfluid (involving correlated atom pairs momentum space) Bose–Einstein condensate (BEC), which spatially local atoms are bound together. This crossover BCS-type BEC limit has long been theoretical interest, motivated part by discovery high-temperature superconductors1,2,3,4,5,6,7,8,9,10. atomic Fermi experiments not yet demonstrated; however, long-lived molecules consisting locally paired fermions have reversibly created11,12,13,14,13. Here we report direct observation molecular created solely adjusting an atoms. state matter one extreme predicted BCS–BEC continuum.