Realization of Rectangular Artificial Spin Ice and Direct Observation of High Energy Topology

Abstract

In this letter, we have constructed and experimentally investigated frustrated arrays of dipoles forming two-dimensional artificial spin ices with different lattice parameters (rectangular arrays with horizontal and vertical lattice spacings denoted by $a$ and $b$ respectively). Arrays with three different ratios $\gamma =a/b=\sqrt{2}$, $\sqrt{3}$ and $\sqrt{4}$ are studied. Theoretical calculations of low-energy demagnetized configurations for these same parameters are also presented. Experimental data for demagnetized samples confirm most of the theoretical results. However, the highest energy topology (doubly-charged monopoles) does not emerge in our theoretical model, while they are seen in experiments for large enough $\gamma$. Our results also insinuate that magnetic monopoles may be almost free in rectangular lattices with a critical ratio $\gamma ={\gamma }_c=\sqrt{3}$, supporting previous theoretical predictions.

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Cited by in corpus (12)

• Ice Rule and Emergent Frustration in Particle Ice and Beyond
• Crystallizing Kagome artificial spin ice
• Experimental and theoretical evidences for the ice regime in planar artificial spin ices
• Thermoplasmonic Nanomagnetic Logic Gates
• Toroidic phase transitions in a direct-kagome artificial spin ice
• Tuning magnetic charge population and mobility in unidirectional array of nanomagnets as a function of lattice parameters
• Naked-eye visualization of geometric frustration effects in macroscopic spin ices
• Bilayer artificial spin ice: magnetic force switching and basic thermodynamics
• Metastability and dynamic modes in magnetic island chains
• Metastability and dynamics in remanent states of square artificial spin ice with long-range dipole interactions
• Topology by Design in Magnetic nano-Materials: Artificial Spin Ice
• Gauge-Free Duality in Pure Square Spin Ice: Topological Currents and Monopoles