Stepwise Positional-Orientational Order and the Multicritical-Multistructural Global Phase Diagram of the s=3/2 Ising Model From Renormalization-Group Theory

Date
2016
Authors
Yunus, Ç.
Renklioǧlu, B.
Keskin, M.
Berker, A. N.
Advisor
Instructor
Source Title
Physical Review E
Print ISSN
2470-0045
Electronic ISSN
Publisher
American Physical Society
Volume
93
Issue
6
Pages
1 - 9
Language
English
Type
Article
Journal Title
Journal ISSN
Volume Title
Abstract

The spin-32 Ising model, with nearest-neighbor interactions only, is the prototypical system with two different ordering species, with concentrations regulated by a chemical potential. Its global phase diagram, obtained in d=3 by renormalization-group theory in the Migdal-Kadanoff approximation or equivalently as an exact solution of a d=3 hierarchical lattice, with flows subtended by 40 different fixed points, presents a very rich structure containing eight different ordered and disordered phases, with more than 14 different types of phase diagrams in temperature and chemical potential. It exhibits phases with orientational and/or positional order. It also exhibits quintuple phase transition reentrances. Universality of critical exponents is conserved across different renormalization-group flow basins via redundant fixed points. One of the phase diagrams contains a plastic crystal sequence, with positional and orientational ordering encountered consecutively as temperature is lowered. The global phase diagram also contains double critical points, first-order and critical lines between two ordered phases, critical end points, usual and unusual (inverted) bicritical points, tricritical points, multiple tetracritical points, and zero-temperature criticality and bicriticality. The four-state Potts permutation-symmetric subspace is contained in this model.

Course
Other identifiers
Book Title
Keywords
Chemical potential, Group theory, Ising model, Lattice theory, Statistical mechanics, Double critical point, Global phase diagrams, Migdal-Kadanoff approximation, Nearest-neighbor interactions, Orientational orderings, Renormalization group, Renormalization group theory, Tetracritical points, Phase diagrams
Citation
Published Version (Please cite this version)