Nonlinear Excitations in Magnetic Lattices with Long-Range Interactions

TL;DR

This paper investigates nonlinear localized excitations called breathers in magnetic lattices with long-range interactions, combining experimental, theoretical, and numerical methods to confirm their existence and decay properties.

Contribution

It provides new experimental and numerical evidence for breathers with crossover decay in magnetic lattices with algebraically-decaying interactions.

Findings

Confirmed existence of breathers with algebraic decay tails.

Demonstrated crossover from exponential to algebraic decay in experiments.

Validated theoretical predictions through numerical simulations.

Abstract

We study - experimentally, theoretically, and numerically - nonlinear excitations in lattices of magnets with long-range interactions. We examine breather solutions, which are spatially localized and periodic in time, in a chain with algebraically-decaying interactions. It was established two decades ago [S. Flach, Phys. Rev. E 58, R4116 (1998)] that lattices with long-range interactions can have breather solutions in which the spatial decay of the tails has a crossover from exponential to algebraic decay. In this Letter, we revisit this problem in the setting of a chain of repelling magnets with a mass defect and verify, both numerically and experimentally, the existence of breathers with such a crossover.