Vortex supersolid in the XY model with tunable vortex fugacity
Year: 2023
Authors: Maccari I., Castellani C., Defenu N., Enss T.
Autors Affiliation: Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden; Swiss Fed Inst Technol, Inst Theoret Phys, Wolfgang-Pauli-Str 27, CH-8093 Zurich, Switzerland; Sapienza Univ Rome, Dept Phys, Ple A Moro 2, I-00185 Rome, Italy; Inst Complex Syst ISC CNR, UOS Sapienza, Ple A Moro 5, I-00185 Rome, Italy; Heidelberg Univ, Inst Theoret Phys, D-69120 Heidelberg, Germany.
Abstract: In this paper, we investigate the XY model in the presence of an additional potential term that independently tunes the vortex fugacity favouring their nucleation. By increasing the strength of this term and thereby the vortex chemical potential mu, we observe significant changes in the phase diagram with the emergence of a normal vortex-antivortex lattice as well as a superconducting vortex-antivortex crystal (lattice supersolid) phase. We examine the transition lines between these two phases and the conventional non-crystalline one as a function of both the temperature and the chemical potential. Our findings suggest the possibility of a peculiar tricritical point where second-order, first-order, and infinite-order transition lines meet. We discuss the differences between the present phase diagram and previous results for two-dimensional Coulomb gas models. Our study provides important insights into the behaviour of the modified XY model and opens up new possibilities for investigating the underlying physics of unconventional phase transitions.
Journal/Review: JOURNAL OF PHYSICS-CONDENSED MATTER
Volume: 35 (33) Pages from: 334001-1 to: 334001-7
More Information: The simulations were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC) at the National Supercomputer Center at Linkoeping, Sweden. I M acknowledges the Carl Trygger foundation through Grant Number CTS 20:75. This work was funded in part by the Swiss National Science Foundation (SNSF) [200021\_207537]. It is also supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Project-ID 273811115 (SFB1225 ISOQUANT) and under Germany’s Excellence Strategy EXC2181/1-390900948 (the Heidelberg STRUCTURES Excellence Cluster).KeyWords: vortex supersolid; XY model; 2D Coulomb gas; BKT phase transition; 2D vortex-antivortex latticeDOI: 10.1088/1361-648X/acd295Citations: 1data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-10-20References taken from IsiWeb of Knowledge: (subscribers only)