title: Observation of phase separation in a strongly interacting imbalanced fermi gas.
abstract: We have observed phase separation between the superfluid and the normal component in a strongly interacting Fermi gas with imbalanced spin populations. The in situ distribution of the density difference between two trapped spin components is obtained using phase-contrast imaging and 3D image reconstruction. A shell structure is clearly identified where the superfluid region of equal densities is surrounded by a normal gas of unequal densities. The phase transition induces a dramatic change in the density profiles as excess fermions are expelled from the superfluid.
authors.affiliation: Department of Physics, MIT-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, USA. yishin@mit.edu
authors.forename: Y
authors.initials: Y
authors.lastname: Shin
authors.forename: M W
authors.initials: MW
authors.lastname: Zwierlein
authors.forename: C H
authors.initials: CH
authors.lastname: Schunck
authors.forename: A
authors.initials: A
authors.lastname: Schirotzek
authors.forename: W
authors.initials: W
authors.lastname: Ketterle