Heat Capacity of a Strongly Interacting Fermi Gas

• Published in: Science (American Association for the Advancement of Science) Vol. 307; no. 5713; pp. 1296 - 1299
• Main Authors: Kinast, Joseph, Turlapov, Andrey, Thomas, John E, Chen, Qijin, Stajic, Jelena, Levin, Kathryn
• Format: Journal Article
• Language: English
• Published: United States American Association for the Advancement of Science 25.02.2005; The American Association for the Advancement of Science
• Subjects: Anisotropy; Atomic interactions; Atoms; Atoms & subatomic particles; Climate; Degenerate matter; Energy; Fermi liquid; Fractions; Gas temperature; Gases; Heat; High temperature superconductivity; Power laws; Scientific Concepts; Specific heat; Strong nuclear force; Superfluidity; Temperature measurement; Thermal properties; Thermodynamics; United States
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1109220

We have measured the heat capacity of an optically trapped, strongly interacting Fermi gas of atoms. A precise addition of energy to the gas is followed by single-parameter thermometry, which determines the empirical temperature parameter of the gas cloud. Our measurements reveal a clear transition in the heat capacity. The energy and the spatial profile of the gas are computed using a theory of the crossover from Fermi to Bose superfluids at finite temperatures. The theory calibrates the empirical temperature parameter, yields excellent agreement with the data, and predicts the onset of superfluidity at the observed transition point.