Degeneracy and criticality from emergent frustration in artificial spin ice

TL;DR

This paper introduces a new artificial spin ice design based on vertex frustration, which exhibits a quasicritical ice phase with extensive residual entropy and algebraic correlations, advancing the understanding of frustration and degeneracy in magnetic nanoarrays.

Contribution

It presents a novel vertex-frustrated artificial spin ice that demonstrates a quasicritical ice phase with algebraic correlations, unlike previous pairwise frustrated systems.

Findings

Exhibits a quasicritical ice phase with extensive residual entropy.

Displays algebraic correlations similar to Coulomb phase.

Provides a new platform for studying defects in critical manifolds.

Abstract

Although initially introduced to mimic the spin-ice pyrochlores, no artificial spin ice has yet exhibited the expected degenerate ice-phase with critical correlations similar to the celebrated Coulomb phase in the pyrochlore lattice. Here we study a novel artificial spin ice based on a vertex-frustrated rather than pairwise frustrated geometry and show that it exhibits a quasicritical ice phase of extensive residual entropy and, significantly, algebraic correlations. Interesting in its own regard as a novel realization of frustration in a vertex system, our lattice opens new pathways to study defects in a critical manifold and to design degeneracy in artificial magnetic nanoarrays, a task so far elusive.