Emergence of Tricritical Point and Liquid-Gas Phase in the Massless 2+1 Dimensional Gross-Neveu Model Auteur(s): Kneur J.-L., Pinto M. B., Ramos R. O., Staudt E. (Article) Publié: Physical Review D, vol. 76 p.045020 (2007) Texte intégral en Openaccess : Ref HAL: in2p3-00148875_v1 Ref Arxiv: 0705.0676 DOI: 10.1103/PhysRevD.76.045020 WoS: 000249155800101 Ref. & Cit.: NASA ADS Exporter : BibTex | endNote 50 Citations Résumé: A complete thermodynamical analysis of the 2+1 dimensional massless Gross-Neveu model is performed using the optimized perturbation theory. This is a non-perturbative method that allows us to go beyond the known large-N results already at lowest order. Our results, for a finite number of fermion species, N, show the existence of a tricritical point in the temperature and chemical potential phase diagram for discrete chiral phase transition allowing us to precisely to locate it. By studying the phase diagram in the pressure and inverse density plane, we also show the existence of a liquid-gas phase, which, so far, was unknown to exist in this model. Finally, we also derive N dependent analytical expressions for the fermionic mass, critical temperature and critical chemical potential. Commentaires: 25 pages, 15 eps figures. Added new references. Minor changes around the text |