Observation of Bose-Einstein condensation in an atomic trap in terms of macroscopic thermodynamic parameters
Authors: Romero-Rochin V., Shiozaki RF., Caracanhas M., Henn EAL., Magalhaes KMF., Roati G., Bagnato VS.
Autors Affiliation: Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, 01000 México, Distrito Federale, Mexico;
Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, 13560-970 São Carlos, São Paulo, Brazil;
INO-CNR and LENS, University of Florence, via N. Carrara 1, 50019 Sesto Fiorentino, Italy
Abstract: To overcome the difficulties in defining pressure for a gas confined in an inhomogeneous trap, we define single macroscopic parameters that behave like pressure and volume. We measure the phase diagram of a Rb-87 Bose gas in a harmonic trap in terms of those macroscopic parameters obtained from the spatial distribution of atoms. Considering the relevant variables such as the trap potential V = (omega(x)omega(y)omega(z))(-1), number of atoms N, and temperature T, a parameter Pi = Pi (N, V, T) is introduced to characterize the overall macroscopic pressure of the system. We construct the phase diagram (Pi vs T) identifying the main features related to the Bose-Einstein condensation (BEC) transition in a trapped gas. A thermodynamic description of the phase transition based on purely macroscopic parameters provides us with a description that does not need the local-density approximation. This procedure can be used to explore different aspects related to BEC such as the nature of the phase transition in a trapped gas.
Journal/Review: PHYSICAL REVIEW A
Volume: 85 (2) Pages from: 023632 to: 023632
More Information: We appreciate collaboration and helpful discussions with J. Seman, P. Castilho, P. Tavares, S. R. Muniz, and G. Telles. The experimental work received financial support from Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, and Coordenacao de Aperfeicoamento de Nivel Superior, Brazil. V.R.-R. acknowledges support from Direccion General de Asuntos del Personal Academico, Universidad Nacional Autonoma de Mexico Grant No. IN-116110.DOI: 10.1103/PhysRevA.85.023632Citations: 7data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2020-05-31References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here