title: Super-Tonks-Girardeau gas of spin-1/2 interacting fermions.
abstract: Fermi gases confined in tight one-dimensional waveguides form two-particle bound states of atoms in the presence of a strongly attractive interaction. Based on the exact solution of the one-dimensional spin-1/2 interacting Fermi gas, we demonstrate that a stable excited state with no pairing between attractive fermionic atoms can be realized by a sudden switch of interaction from the strongly repulsive regime to strongly attractive regime. Such a state is an exact fermionic analog of the experimentally observed super-Tonks-Girardeau state of bosonic Cesium atoms [Science 325, 1224 (2009)] and should be possible to be observed by the experiment. The frequency of the lowest breathing mode of the fermionic super-Tonks-Girardeau gas is calculated as a function of the interaction strength, which could be used as a detectable signature for the experimental observation.
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Liming
authors.initials: L
authors.lastname: Guan
authors.forename: Shu
authors.initials: S
authors.lastname: Chen