title: Inverse melting and inverse freezing in a three-state spin-glass model with finite connectivity.
abstract: The phase diagrams of the three-state Ghatak-Sherrington spin-glass (or random Blume-Capel) model are obtained in mean-field theory with replica symmetry in order to study the effects of a ferromagnetic bias and finite random connectivity in which each spin is connected to a finite number of other spins. It is shown that inverse melting from a ferromagnetic to a low-temperature paramagnetic phase may appear for small but finite disorder and that inverse freezing appears for large disorder. There can also be a continuous inverse ferromagnetic to spin-glass transition.
authors: Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, 91501-970 Porto Alegre, RS, Brazil. rubem@if.ufrgs.br
authors: R
authors: R
authors: Erichsen
authors: W K
authors: WK
authors: Theumann
authors: S G
authors: SG
authors: Magalhaes
mesh_terms: D003198:Computer Simulation; D004735:Energy Transfer; D060526:Magnetic Fields; D008956:Models, Chemical; D008958:Models, Molecular; D015233:Models, Statistical; D044367:Phase Transition; D012542:Scattering, Radiation