Complex Critical Exponents for Percolation Transitions in Josephson-Junction Arrays, Antiferromagnets, and Interacting Bosons

TitleComplex Critical Exponents for Percolation Transitions in Josephson-Junction Arrays, Antiferromagnets, and Interacting Bosons
Publication TypeJournal Article
Year of Publication2011
AuthorsFernandes RM, Schmalian J
Journal TitlePhysical Review Letters
Volume106
Pages067004
Date Published02
Type of ArticleArticle
ISBN Number0031-9007
Accession NumberISI:000287357100019
Abstract

We show that the critical behavior of the XY quantum-rotor model undergoing a percolation transition is dramatically affected by its topological Berry phase 2 pi rho. In particular, for irrational rho, its low-energy excitations emerge as spinless fermions with fractal spectrum. As a result, critical properties not captured by the usual Ginzburg-Landau-Wilson description of phase transitions arise, such as complex critical exponents, log-periodic oscillations and dynamically broken scale invariance.

URL<Go to ISI>://000287357100019
DOI10.1103/PhysRevLett.106.067004
Alternate JournalPhys. Rev. Lett.