2005/01/31 by A. P. Mosk · 1 citation
Physics and Astronomy · #cond-mat.stat-mech
paper · pdf · doi:10.1103/physrevlett.95.040403
published as Phys. Rev. Lett. 95, 040403 (2005) · 4 pages 5 figures; v4: Typo corrections. Accepted Phys. Rev. Lett
arxiv created 2005/07/04 · arxiv updated 2009/12/01
We show that thermalization of the motion of atoms at negative temperature is possible in an optical lattice, for conditions that are feasible in current experiments. We present a method for reversibly inverting the temperature of a trapped gas. Moreover, a negative-temperature ensemble can be cooled, reducing abs(T), by evaporation of the lowest-energy particles. This enables the attainment of the Bose-Einstein condensation phase transition at negative temperature.