RT Journal Article
SR Electronic
T1 Measurement of Universal Thermodynamic Functions for a Unitary Fermi Gas
JF Science
JO Science
FD American Association for the Advancement of Science
SP 442
OP 445
DO 10.1126/science.1183012
VO 327
IS 5964
A1 Horikoshi, Munekazu
A1 Nakajima, Shuta
A1 Ueda, Masahito
A1 Mukaiyama, Takashi
YR 2010
UL http://science.sciencemag.org/content/327/5964/442.abstract
AB Thermodynamic properties of matter generally depend on the details of interactions between its constituent parts. However, in a unitary Fermi gas where the scattering length diverges, thermodynamics is determined through universal functions that depend only on the particle density and temperature. By using only the general form of the equation of state and the equation of force balance, we measured the local internal energy of the trapped gas as a function of these parameters. Other universal functions, such as those corresponding to the Helmholtz free energy, chemical potential, and entropy, were calculated through general thermodynamic relations. The critical parameters were also determined at the superfluid transition temperature. These results apply to all strongly interacting fermionic systems, including neutron stars and nuclear matter.