Cooper pairing and BCS-BEC evolution in mixed-dimensional Fermi gases

Journal Article · Wed Dec 15 04:00:00 EST 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.063628· OSTI ID:21528951

Iskin, M; Subasi, A L ^[1]

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1. Department of Physics, Koc University, Rumelifeneri Yolu, 34450 Sariyer, Istanbul (Turkey)

Similar to what has recently been achieved with Bose-Bose mixtures [G. Lamporesi, J. Catani, G. Barontini, Y. Nishida, M. Inguscio, and F. Minardi, Phys. Rev. Lett. 104, 153202 (2010)], mixed-dimensional Fermi-Fermi mixtures can be created by applying a species-selective one-dimensional optical lattice to a two-species Fermi gas ({sigma}{identical_to}({up_arrow},{down_arrow})), in such a way that both species are confined to quasi-two-dimensional geometries determined by their hoppings along the lattice direction. We investigated the ground-state phase diagram of superfluidity for such mixtures in the BCS-BEC evolution, and found normal, gapped superfluid, gapless superfluid, and phase separated regions. In particular, we found a stable gapless superfluid phase where the unpaired {up_arrow} and {down_arrow} fermions coexist with the paired (or superfluid) ones in different momentum space regions. This phase is in some ways similar to the Sarma state found in mixtures with densities, but in our case, the gapless superfluid phase is unpolarized and most importantly it is stable against phase separation.

• OSTI ID: 21528951
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 6 Vol. 82; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
BOSE-EINSTEIN CONDENSATION
COOPER PAIRS
DIAGRAMS
FERMI GAS
FERMIONS
GEOMETRY
INFORMATION
MATHEMATICS
ONE-DIMENSIONAL CALCULATIONS
PHASE DIAGRAMS
SUPERFLUIDITY
TWO-DIMENSIONAL CALCULATIONS