Berezinskii-Kosterlitz-Thouless paired phase in coupled XY models

Bighin, Giacomo; Defenu, Nicolò; Nándori, István; Salasnich, Luca; Trombettoni, Andrea

Berezinskii-Kosterlitz-Thouless paired phase in coupled XY models

Bighin G, Defenu N, Nándori I, Salasnich L, Trombettoni A. 2019. Berezinskii-Kosterlitz-Thouless paired phase in coupled XY models. Physical Review Letters. 123(10), 100601.

Download (ext.)

https://arxiv.org/abs/1907.06253

DOI

10.1103/physrevlett.123.100601

Journal Article | Published | English

Scopus indexed

Author

Bighin, Giacomo^ISTA ; Defenu, Nicolò; Nándori, István; Salasnich, Luca; Trombettoni, Andrea

Department

Lemeshko Group

Grant

A path-integral approach to composite impurities

Abstract

We study the effect of a linear tunneling coupling between two-dimensional systems, each separately exhibiting the topological Berezinskii-Kosterlitz-Thouless (BKT) transition. In the uncoupled limit, there are two phases: one where the one-body correlation functions are algebraically decaying and the other with exponential decay. When the linear coupling is turned on, a third BKT-paired phase emerges, in which one-body correlations are exponentially decaying, while two-body correlation functions exhibit power-law decay. We perform numerical simulations in the paradigmatic case of two coupled XY models at finite temperature, finding evidences that for any finite value of the interlayer coupling, the BKT-paired phase is present. We provide a picture of the phase diagram using a renormalization group approach.

Publishing Year

2019

Date Published

2019-09-06

Journal Title

Physical Review Letters

Acknowledgement

We thank S. Chiacchiera, G. Delfino, N. Dupuis, T. Enss, M. Fabrizio and G. Gori for many stimulating discussions. G.B. acknowledges support from the Austrian Science Fund (FWF), under project No. M2461-N27. N.D. acknowledges support from Deutsche Forschungsgemeinschaft (DFG) under Germany’s Excellence Strategy EXC-2181/1 - 390900948 (the Heidelberg STRUCTURES Excellence Cluster) and from the DFG Collaborative Research Centre “SFB 1225 ISOQUANT”. Support from the CNR/MTA Italy-Hungary 2019-2021 Joint Project “Strongly interacting systems in confined geometries” is gratefully acknowledged.

Volume

123

Issue

Article Number

100601

ISSN

0031-9007

eISSN

1079-7114

IST-REx-ID

6940

Cite this

Bighin G, Defenu N, Nándori I, Salasnich L, Trombettoni A. Berezinskii-Kosterlitz-Thouless paired phase in coupled XY models. Physical Review Letters. 2019;123(10). doi:10.1103/physrevlett.123.100601

Bighin, G., Defenu, N., Nándori, I., Salasnich, L., & Trombettoni, A. (2019). Berezinskii-Kosterlitz-Thouless paired phase in coupled XY models. Physical Review Letters. American Physical Society. https://doi.org/10.1103/physrevlett.123.100601

Bighin, Giacomo, Nicolò Defenu, István Nándori, Luca Salasnich, and Andrea Trombettoni. “Berezinskii-Kosterlitz-Thouless Paired Phase in Coupled XY Models.” Physical Review Letters. American Physical Society, 2019. https://doi.org/10.1103/physrevlett.123.100601.

G. Bighin, N. Defenu, I. Nándori, L. Salasnich, and A. Trombettoni, “Berezinskii-Kosterlitz-Thouless paired phase in coupled XY models,” Physical Review Letters, vol. 123, no. 10. American Physical Society, 2019.

Bighin G, Defenu N, Nándori I, Salasnich L, Trombettoni A. 2019. Berezinskii-Kosterlitz-Thouless paired phase in coupled XY models. Physical Review Letters. 123(10), 100601.

Bighin, Giacomo, et al. “Berezinskii-Kosterlitz-Thouless Paired Phase in Coupled XY Models.” Physical Review Letters, vol. 123, no. 10, 100601, American Physical Society, 2019, doi:10.1103/physrevlett.123.100601.

All files available under the following license(s):

Copyright Statement: