Universal behavior of coupled order parameters below three dimensions

• Verfasst von: Borchardt, Julia [VerfasserIn]
• Verfasst von: Eichhorn, Astrid [VerfasserIn]
• Titel: Universal behavior of coupled order parameters below three dimensions
• Verf.angabe: Julia Borchardt and Astrid Eichhorn
• Fussnoten: Gesehen am 21.11.2017
• Titel Quelle: Enthalten in: Physical review
• Jahr Quelle: 2016
• Band/Heft Quelle: 94(2016,4) Artikel-Nummer 042105, 16 Seiten
• ISSN Quelle: 2470-0053
• DOI: doi:10.1103/PhysRevE.94.042105
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1565583434

Abstract

We explore universal critical behavior in models with two competing order parameters, and an O(N) ⊕O(M) symmetry for dimensions d≤3. In d=3, there is always exactly one stable renormalization group fixed point, corresponding to bicritical or tetracritical behavior. Employing pseudospectral techniques to solve functional renormalization group equations in a two-dimensional field space, we uncover a more intricate structure of fixed points in d<3, where two additional bicritical fixed points play a role. Towards d=2, we discover ranges of N=M with several simultaneously stable fixed points, indicating the coexistence of several universality classes.