Artificial molecules

Superfluids are normally described by a real wave function. The spontaneous breaking of the time-reversal symmetry due to pair tunneling leads to a twist in the complex phase ...

Nature Physics 8, 71–75 (2012),
Scientific Reports 5, 12912 (2015)

While conventional tunneling is “only single-particle physics”, we identify an interaction-driven tunneling process for atoms in optical lattices. While this possibility was discussed for solids, it could never have been observed directly. In optical lattices, this kind of tunneling is pronounced...