Breakdown of Universality for Unequal-Mass Fermi Gases with Infinite Scattering Length

Journal Article · Fri Oct 22 00:00:00 EDT 2010 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.105.170403· OSTI ID:21467029

Blume, D; Daily, K M ^[1]

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1. Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States)

We treat small trapped unequal-mass two-component Fermi gases at unitarity within a nonperturbative microscopic framework and investigate the system properties as functions of the mass ratio {kappa}, and the numbers N{sub 1} and N{sub 2} of heavy and light fermions. While equal-mass Fermi gases with infinitely large interspecies s-wave scattering length a{sub s} are universal, we find that unequal-mass Fermi gases are, for sufficiently large {kappa} and in the regime where Efimov physics is absent, not universal. In particular, the (N{sub 1},N{sub 2})=(2,1) and (3, 1) systems exhibit three-body and four-body resonances at {kappa}=12.314(2) and 10.4(2), respectively, as well as surprisingly large finite-range effects. These findings have profound implications for ongoing experimental efforts and quantum simulation proposals that utilize unequal-mass atomic Fermi gases.

• OSTI ID: 21467029
• Journal Information: Physical Review Letters, Vol. 105, Issue 17; Other Information: DOI: 10.1103/PhysRevLett.105.170403; (c) 2010 American Institute of Physics; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
COMPUTERIZED SIMULATION
FERMI GAS
FERMIONS
FOUR-BODY PROBLEM
MASS
QUANTUM MECHANICS
RESONANCE
S WAVES
SCATTERING LENGTHS
THREE-BODY PROBLEM
TRAPPING
UNITARITY
DIMENSIONS
LENGTH
MANY-BODY PROBLEM
MECHANICS
PARTIAL WAVES
SIMULATION