arXiv:cond-mat/0701692 · Physical Review B

Spinodal decomposition in polarized Fermi superfluids

Austen Lamacraft, Francesca Maria Marchetti

Published Jan 17, 2008• 16 citations

Abstract

We discuss the dynamics of phase separation through the process of spinodal decomposition in a Fermi superfluid with population imbalance. We discuss this instability first in terms of a phenomenological Landau theory. Working within the mean-field description at zero temperature, we then find the spinodal region in the phase diagram of polarization versus interaction strength and the spectrum of unstable modes in this region. After a quench, the spinodal decomposition starts from the Sarma state, which is a minimum of the free energy with respect to the order parameter at fixed density and polarization and a maximum at fixed chemical potentials. The possibility of observing nontrivial domain structures in current experiments with trapped atomic gases is discussed.

DOI: 10.1103/physrevb.77.014511

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