Ice, glass, and solid phases in artificial spin systems with quenched disorder

TL;DR

This study investigates a disordered artificial spin-ice system that transitions from ordered square ice to a topologically degenerate shakti ice, revealing a spin-glass phase due to geometrical frustration and quenched disorder.

Contribution

It introduces a tunable artificial spin system with controlled disorder, bridging ordered and topologically degenerate phases, and explores the emergence of a spin-glass regime.

Findings

Disorder disrupts long-range order in square ice.

System exhibits a topological phase similar to the Rys F-model.

A spin-glass phase emerges at low temperatures due to frustration.

Abstract

We present a numerical study on a disordered artificial spin-ice system which interpolates between the long-range ordered square ice and the fully degenerate shakti ice. Starting from the square-ice geometry, disorder is implemented by adding vertical/horizontal magnetic islands to the center of some randomly chosen square plaquettes of the array, at different densities. When no island is added we have ordered square ice. When all square plaquettes have been modified we obtain shakti ice, which is disordered yet in a topological phase corresponding to the Rys F-model. In between, geometrical frustration due to these additional center spins disrupts the long-range Ising order of square-ice, giving rise to a spin-glass regime at low temperatures. The artificial spin system proposed in our work provides an experimental platform to study the interplay between quenched disorder and geometrical frustration.