Abstract
Atoms with different internal states can exhibit different responses to an artificial magnetic field. An atomic gas mixture of two different components can therefore be interpreted as a mixture of two atomic gases carrying different synthetic charges. We consider the superfluid state of such unequally charged Fermi gases coupled to a magnetic field via the orbital effect and trapped in a torus geometry. The orbital coupling to the magnetic field favors an inhomogeneous superfluid state with optimum finite-center-of-mass-momentum pairing. The resulting population-balanced orbital Fulde-Ferrell (FF) state is robust against the magnetic field and does not undergo pair breaking, unlike the conventional BCS and Fulde-Ferrell-Larkin-Ovchinnikov-type pairing states under the Zeeman effect. We contrast the homogeneous and inhomogeneous cases, emphasizing the advantages of the unequally charged systems, and present their momentum distributions. We conclude that an unequally charged atomic Fermi gas system orbitally coupled to an artificial magnetic field provides an ideal candidate for experimental realization of the FF state.
| Original language | English |
|---|---|
| Article number | 053614 |
| Journal | Physical Review A |
| Volume | 101 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - May 2020 |
Bibliographical note
Publisher Copyright:© 2020 American Physical Society.
Funding
This work was supported by MSGSÜ BAP under Project No. 2019-26. A.L.S. acknowledges the scholarship program by TÜBİTAK BİDEB 2219 and the hospitality of the Center for Non-linear Studies supported by the Laboratory Directed Research and Development program of Los Alamos National Laboratory under Project No. 20180045DR. The authors acknowledge useful discussions with R. Onur Umucalılar. This work was supported by MSGSU BAP under Project No. 2019-26. A.L.S. acknowledges the scholarship program by TUBITAK BIDEB 2219 and the hospitality of the Center for Non-linear Studies supported by the Laboratory Directed Research and Development program of Los Alamos National Laboratory under Project No. 20180045DR. The authors acknowledge useful discussions with R. Onur Umucalilar.
| Funders | Funder number |
|---|---|
| MSGSU BAP | |
| MSGSÜ BAP | 2019-26 |
| TUBITAK | BIDEB 2219 |
| TÜBİTAK | |
| Laboratory Directed Research and Development | |
| Los Alamos National Laboratory | 20180045DR |