title: Verification of universal relations in a strongly interacting Fermi gas.
abstract: Many-body fermion systems are important in many branches of physics, including condensed matter, nuclear, and now cold atom physics. In many cases, the interactions between fermions can be approximated by a contact interaction. A recent theoretical advance in the study of these systems is the derivation of a number of exact universal relations that are predicted to be valid for all interaction strengths, temperatures, and spin compositions. These equations, referred to as the Tan relations, relate a microscopic quantity, namely, the amplitude of the high-momentum tail of the fermion momentum distribution, to the thermodynamics of the many-body system. In this work, we provide experimental verification of the Tan relations in a strongly interacting gas of fermionic atoms by measuring both the microscopic and macroscopic quantities in the same system.
authors.affiliation: JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, USA.
authors.forename: J T
authors.initials: JT
authors.lastname: Stewart
authors.forename: J P
authors.initials: JP
authors.lastname: Gaebler
authors.forename: T E
authors.initials: TE
authors.lastname: Drake
authors.forename: D S
authors.initials: DS
authors.lastname: Jin