Berezinskii-Kosterlitz-Thouless Phase Transitions with Long-Range Couplings

Year: 2021

Authors: Giachetti G., Defenu N., Ruffo S., Trombettoni A.

Autors Affiliation: SISSA, Via Bonomea 265, I-34136 Trieste, Italy; Ist Nazl Fis Nucl, Sez Trieste, Via Bonomea 265, I-34136 Trieste, Italy; Swiss Fed Inst Technol, Inst Theoret Phys, Wolfgang Pauli Str 27, CH-8093 Zurich, Switzerland; CNR, Ist Sistemi Complessi, Via Madonna Piano 10, I-50019 Sesto Fiorentino, Italy; Univ Trieste, Dept Phys, Str Costiera 11, I-34151 Trieste, Italy; CNR, IOM DEMOCRITOS Simulat Ctr, Via Bonomea 265, I-34136 Trieste, Italy.

Abstract: The Berezinskii-Kosterlitz-Thouless (BKT) transition is the paradigmatic example of a topological phase transition without symmetry breaking, where a quasiordered phase, characterized by a power-law scaling of the correlation functions at low temperature, is disrupted by the proliferation of topological excitations above the critical temperature T-BKT. In this Letter, we consider the effect of long-range decaying couplings similar to r(-2-sigma )on the BKT transition. After pointing out the relevance of this nontrivial problem, we discuss the phase diagram, which is far richer than the corresponding short-range one. It features-for 7/4 < sigma < 2-a quasiordered phase in a finite temperature range T-c < T < T-BKT, which occurs between a symmetry broken phase for T < T-c and a disordered phase for T > T-BKT. The transition temperature T-c displays unique universal features quite different from those of the traditional, short-range XY model. Given the universal nature of our findings, they may be observed in current experimental realizations in 2D atomic, molecular, and optical quantum systems.

Journal/Review: PHYSICAL REVIEW LETTERS

Volume: 127 (15)      Pages from: 156801-1  to: 156801-7

More Information: Valuable discussions with G. Parisi, F. Ricci-Tersenghi, and A. Scardicchio are gratefully acknowledged. N. D. and A. T. also acknowledge useful discussion with M. Ibanez Berganza. This work is supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy EXC2181/1-390900948 (the Heidelberg STRUCTURES Excellence Cluster). This work is supported by the CNR/HAS (Italy-Hungary) project Strongly interacting systems in confined geometries. This work is part of Ministero dell’Universita e della Ricerca, MUR-PRIN2017 proj ect Coarse-grained description for nonequilibrium systems and transport phenomena (CONEST) No. 201798CZL, whose partial financial support is acknowledged.
KeyWords: Coulomb Gas; Plane; Order; Renormalization; Magnetization; Ferromagnets; Propagation; Crossover; Duality; Systems
DOI: 10.1103/PhysRevLett.127.156801

Citations: 23
data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-10-20
References taken from IsiWeb of Knowledge: (subscribers only)