Mean-field study of itinerant ferromagnetism in trapped ultracold Fermi gases: Beyond the local-density approximation

Journal Article · Thu Jul 15 00:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.013627· OSTI ID:21442976

Dong, H ^[1]; Hui, Hu; Xiaji, Liu; Drummond, Peter D ^[1]

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1. ARC Centre of Excellence for Quantum-Atom Optics, Centre for Atom Optics and Ultrafast Spectroscopy, Swinburne University of Technology, Melbourne 3122 (Australia)

We theoretically investigate the itinerant ferromagnetic transition of a spherically trapped ultracold Fermi gas with spin imbalance under strongly repulsive interatomic interactions. Our study is based on a self-consistent solution of the Hartree-Fock mean-field equations beyond the widely used local-density approximation. We demonstrate that, while the local-density approximation holds in the paramagnetic phase, after the ferromagnetic transition it leads to a quantitative discrepancy in various thermodynamic quantities even with large atom numbers. We determine the position of the phase transition by monitoring the shape change of the free-energy curve with increasing the polarization at various interaction strengths.

• OSTI ID: 21442976
• Journal Information: Physical Review. A, Vol. 82, Issue 1; Other Information: DOI: 10.1103/PhysRevA.82.013627; (c) 2010 The American Physical Society; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
74 ATOMIC AND MOLECULAR PHYSICS
DENSITY
FERMI GAS
FERROMAGNETISM
FIELD EQUATIONS
FREE ENERGY
HARTREE-FOCK METHOD
MATHEMATICAL SOLUTIONS
MEAN-FIELD THEORY
PARAMAGNETISM
PHASE TRANSFORMATIONS
POLARIZATION
SPIN
TRAPPING
ANGULAR MOMENTUM
APPROXIMATIONS
CALCULATION METHODS
ENERGY
EQUATIONS
MAGNETISM
PARTICLE PROPERTIES
PHYSICAL PROPERTIES
THERMODYNAMIC PROPERTIES