Year: 2019
Type: article
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.
Source: Physical Review Letters
Institutions: Institute of Science and Technology Austria, Heidelberg University, University of Debrecen, HUN-REN Institute for Nuclear Research, Institute for Particle and Nuclear Physics, University of Padua, National Institute of Optics, National Research Council, Scuola Internazionale Superiore di Studi Avanzati, Istituto Officina dei Materiali, Istituto Nazionale di Fisica Nucleare, Sezione di Trieste
Language: Latvian
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2957723666