Microscopic Observation of Non-Ergodic States in Two-Dimensional Non-Topological Bubble Lattices

TL;DR

This paper investigates the properties of non-ergodic, glassy states in disordered two-dimensional magnetic bubble lattices, revealing how external fields stabilize these states and affect lattice defects and dynamics.

Contribution

It introduces a controlled method to create and analyze non-topological magnetic bubble lattices in a ferrimagnetic alloy, highlighting their non-ergodic glassy behavior.

Findings

Identification of dislocation defects in the lattice

Observation of non-ergodic, glassy state stabilization

Analysis of lattice dynamics under external fields

Abstract

Disordered 2D lattices, including hexatic and various glassy states, are observed in a wide range of 2D systems including colloidal nanoparticle assemblies and fluxon lattices. Their disordered nature determines the stability and mobility of these systems, as well as their response to the external stimuli. Here we report on the controlled creation and characterization of a disordered 2D lattice of non-topological magnetic bubbles in the non-centrosymmetric ferrimagnetic alloy Mn$_{1.4}$PtSn. By analyzing the type and frequency of fundamental lattice defects, such as dislocations, the orientational correlation, as well as the induced motion of the lattice in an external field, a non-ergodic glassy state, stabilized by directional application of an external field, is revealed.