Phase Diagram of a Polarized Fermi Gas Across a Feshbach

ORAL

Abstract

We investigate a Fermi gas of $^6$Li atoms with unbalanced populations in two spin states, whose interactions are tuned by a Feshbach resonance. At the unitarity limit, we observe three distinct phases connected by a tricritical point on a polarization vs. temperature (\textit{P}-\textit{T}) phase diagram: a phase-separated state at low \textit{T}, a polarized superfluid and a polarized normal gas at higher \textit{T}. We are currently mapping out the phase diagram as a function of \textit{P}, \textit{T} and interaction. At \textit{T} = 0, as the interaction strength is tuned toward the BEC side of the resonance, we expect to encounter a phase boundary between the phase-separated state and the polarized superfluid. Conversely, on the BCS side, for finite \textit{P}, a transition to the polarized normal gas is expected. We will present our latest results.

Authors

  • Wenhui Li

    Department of Physics and Astronomy and Rice Quantum Institute, Rice University, Houston, TX 77251, USA

  • Yean-an Liao

    Department of Physics and Astronomy and Rice Quantum Institute, Rice University

  • Guthrie B. Partridge

    Department of Physics and Astronomy and Rice Quantum Institute, Rice University

  • R.G. Hulet

    Department of Physics and Astronomy and Rice Quantum Institute, Rice University