Free Fermi gas dynamics with orbital interactions in ultracold Yb

Bo Song, Chengdong He, Elnur Hajiyev +6 more

S Mondal, D Inotani, Y Ohashi

We theoretically investigate strong-coupling properties of an ultracold Fermi gas with an orbital Feshbach resonance (OFR). Including tunable pairing interaction associated with an OFR within the framework of the strong-coupling theory developed by Nozières and Schmitt-Rink (NSR), we examine the occupation of the closed channel. We show that, although the importance of the closed channel is characteristic of the system with an OFR, the occupation number of the closed channel is found to actually be very small at the superfluid phase transition temperature T c , in the whole BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover region, when we use the scattering parameters for an ultracold 173 Yb Fermi gas. The occupation of the closed channel increases with increasing the temperature above T c , which is more remarkable for a stronger pairing interaction. We also present a prescription to remove effects of an experimentally inaccessible deep bound state from the NSR formalism, which we meet when we theoretically deal with a 173 Yb Fermi gas with an OFR.

Guido Pagano, M. Mancini, Giacomo Cappellini +5 more

We report on the experimental observation of a strongly interacting gas of ultracold two-electron fermions with an orbital degree of freedom and magnetically tunable interactions. This realization has been enabled by the demonstration of a novel kind of Feshbach resonance occurring in the scattering of two (173)Yb atoms in different nuclear and electronic states. The strongly interacting regime at resonance is evidenced by the observation of anisotropic hydrodynamic expansion of the two-orbital Fermi gas. These results pave the way towards the realization of new quantum states of matter with strongly correlated fermions with an orbital degree of freedom.

M. Kronenwett, T. Gasenzer

Simon L. Cornish

We report on the experimental observation of a strongly interacting gas of ultracold two-electron fermions with an orbital degree of freedom and magnetically tunable interactions.This realization has been enabled by the demonstration of a novel kind of Feshbach resonance occurring in the scattering of two 173 Yb atoms in different nuclear and electronic states.The strongly interacting regime at resonance is evidenced by the observation of anisotropic hydrodynamic expansion of the two-orbital Fermi gas.These results pave the way towards the realization of new quantum states of matter with strongly correlated fermions with an orbital degree of freedom.

Dovran Amanov, Cai, geyue, Chengdong He +4 more