Nonperturbative renormalization group treatment of amplitude fluctuations for [phi]4 topological phase transitions

The study of the Berezinskii-Kosterlitz-Thouless transition in two-dimensional |φ|4 models can be performed in several representations, and the amplitude-phase (AP) Madelung parametrization is a natural way to study the contribution of density fluctuations to nonuniversal quantities. We introduce a...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Defenu, Nicolò (VerfasserIn) , Enss, Tilman (VerfasserIn)
Dokumenttyp: Article (Journal)
Sprache:Englisch
Veröffentlicht: 13 November 2017
In: Physical review
Year: 2017, Jahrgang: 96, Heft: 17
ISSN:2469-9969
DOI:10.1103/PhysRevB.96.174505
Online-Zugang:Verlag, Volltext: http://dx.doi.org/10.1103/PhysRevB.96.174505
Verlag, Volltext: https://link.aps.org/doi/10.1103/PhysRevB.96.174505
Volltext
Verfasserangaben:Nicolò Defenu, Andrea Trombettoni, István Nándori, and Tilman Enss
Beschreibung
Zusammenfassung:The study of the Berezinskii-Kosterlitz-Thouless transition in two-dimensional |φ|4 models can be performed in several representations, and the amplitude-phase (AP) Madelung parametrization is a natural way to study the contribution of density fluctuations to nonuniversal quantities. We introduce a functional renormalization group scheme in AP representation where amplitude fluctuations are integrated first to yield an effective sine-Gordon model with renormalized superfluid stiffness. By a mapping between the lattice XY and continuum |φ|4 models, our method applies to both on equal footing. Our approach correctly reproduces the existence of a line of fixed points and of universal thermodynamics and it allows to estimate universal and nonuniversal quantities of the two models, finding good agreement with available Monte Carlo results. The presented approach is flexible enough to treat parameter ranges of experimental relevance.
Beschreibung:Im Titel ist „4“ hochgestellt, Phi als griechischer Buchstabe und zwischen zwei senkrechten Strichen dargestellt
Gesehen am 23.11.2017
Beschreibung:Online Resource
ISSN:2469-9969
DOI:10.1103/PhysRevB.96.174505