Exploring the interplay between fractionality and PT symmetry in magnetic metamaterials

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Molina, Mario I.
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917948511223808
author Molina, Mario I.
author_facet Molina, Mario I.
contents We study a nonlinear magnetic metamaterial modeled as a split-ring resonator array, where the standard discrete laplacian is replaced by its fractional form. We find a closed-form expression for the dispersion relation as a function of the fractional exponent s and the gain/loss parameter γ and examine the conditions under which stable magneto-inductive waves exist. The density of states is computed in closed form and suggests that the main effect of fractionality is the flattening of the bands, while gain/loss increase tends to reduce the bandgaps. The spatial extent of the modes for a finite array is computed by means of the participation ratio R, which is also obtained in closed form. For a fixed fractionality exponent, an increase in gain/loss γ decreases the overall R, from the number of sites N towards N/2 at large γ. The nonlinear dynamics of the average magnetic energy on an initial ring during a cycle shows a monotonic increase with γ, and it is qualitatively similar for all fractional exponents. This is explained as mainly due to the interplay of nonlinearity and PT symmetry.
format Preprint
id arxiv_https___arxiv_org_abs_2503_06289
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Exploring the interplay between fractionality and PT symmetry in magnetic metamaterials
Molina, Mario I.
Pattern Formation and Solitons
We study a nonlinear magnetic metamaterial modeled as a split-ring resonator array, where the standard discrete laplacian is replaced by its fractional form. We find a closed-form expression for the dispersion relation as a function of the fractional exponent s and the gain/loss parameter γ and examine the conditions under which stable magneto-inductive waves exist. The density of states is computed in closed form and suggests that the main effect of fractionality is the flattening of the bands, while gain/loss increase tends to reduce the bandgaps. The spatial extent of the modes for a finite array is computed by means of the participation ratio R, which is also obtained in closed form. For a fixed fractionality exponent, an increase in gain/loss γ decreases the overall R, from the number of sites N towards N/2 at large γ. The nonlinear dynamics of the average magnetic energy on an initial ring during a cycle shows a monotonic increase with γ, and it is qualitatively similar for all fractional exponents. This is explained as mainly due to the interplay of nonlinearity and PT symmetry.
title Exploring the interplay between fractionality and PT symmetry in magnetic metamaterials
topic Pattern Formation and Solitons
url https://arxiv.org/abs/2503.06289