Collapse transition in mixtures of bosons and fermions

Journal Article · Thu Apr 01 04:00:00 EST 2004 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.69.043607· OSTI ID:20641026

Chui, S T ^[1]; Ryzhov, V N ^[2]

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1. Bartol Research Institute, University of Delaware, Newark, Delaware 19716 (United States)
2. Institute for High Pressure Physics, Russian Academy of Sciences 142190 Troitsk (Russian Federation)

For mixtures of Bose and Fermi alkali-metal atoms, the fermion degrees of freedom can be integrated out in their finite temperature partition function. The final result can be expanded as a power series in the boson density. Under appropriate conditions, the pairwise interaction between the bosons can be changed from positive to negative by the fermion-mediated term at a low enough temperature. The boson cloud may then collapse. For attractive fermion-boson interactions, there is also a collapse of the fermion cloud. This transition is first order (discontinuous) because the leading-order nonlinear interaction term between the bosons is third order in boson density with a negative coefficient. We discuss the finite-temperature phase diagram of this transition. Our result may provide for an explanation of recent experimental observations by Modugno and co-workers.

• OSTI ID: 20641026
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 69; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ALKALI METALS
ATOM-ATOM COLLISIONS
ATOMS
BOSONS
DEGREES OF FREEDOM
DENSITY
FERMIONS
MIXTURES
NONLINEAR PROBLEMS
PARTITION FUNCTIONS
PHASE DIAGRAMS
POWER SERIES
RADIATION PRESSURE