Local atom-number fluctuations in quantum gases at finite temperature
Authors: Klawunn M., Recati A., Pitaevskii L.P., Stringari S.
Autors Affiliation: INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, I-38123 Povo, Italy;
Kapitza Institute for Physical Problems, Russian Academy of Science, Kosygin Street 2, 119334 Moscow, Russia
Abstract: We investigate the number fluctuations in small cells of quantum gases pointing out important deviations from the thermodynamic limit fixed by the isothermal compressibility. Both quantum and thermal fluctuations in weakly as well as highly compressible fluids are considered. For the two-dimensional (2D) superfluid Bose gas we find a significant quenching of fluctuations with respect to the thermodynamic limit, in agreement with recent experimental findings. An enhancement of the thermal fluctuations is instead predicted for the 2D dipolar superfluid Bose gas, which becomes dramatic when the size of the sample cell is of the order of the wavelength of the rotonic excitation induced by the interaction.
Journal/Review: PHYSICAL REVIEW A
Volume: 84 (3) Pages from: 033612 to: 033612
More Information: We acknowledge very useful discussion with C. Chin, T. Esslinger, W. Ketterle, S. Muller, and G. Shlyapnikov. This work has been supported by ERC through the QGBE grant.DOI: 10.1103/PhysRevA.84.033612Citations: 32data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2021-05-09References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here