Magnetic-Field-Dependent Thermodynamic Properties of Square and Quadrupolar Artificial Spin Ice

Abstract

Applied magnetic fields are an important tuning parameter for artificial spin ice (ASI) systems, as they can drive phase transitions between different magnetic ground states, or tune through regimes with high populations of emergent magnetic excitations (e.g., monopole-like quasiparticles). Here, using simulations supported by experiments, we investigate the thermodynamic properties and magnetic phases of square and quadrupolar ASI as a function of applied in-plane magnetic fields. Monte Carlo simulations are used to generate field-dependent maps of the magnetization, the magnetic specific heat, the thermodynamic magnetization fluctuations, and the magnetic order parameters, all under equilibrium conditions. These maps reveal the diversity of magnetic orderings and the phase transitions that occur in different regions of the phase diagrams of these ASIs, and are experimentally supported by magneto-optical measurements of the equilibrium "magnetization noise" in thermally-active ASIs.

12 pages, 7 figures, in press at Physical Review B

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• Artificial square ice and related dipolar nanoarrays
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Cited by in corpus (7)

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• Deconstructing Magnetization Noise: Degeneracies, Phases, and Mobile Fractionalized Excitations in Tetris Artificial Spin Ice
• Relaxation pathways and emergence of domains in square artificial spin ice
• Complex field reversal dynamics in nanomagnetic systems
• Attaining the Ground State of Kagome Artificial Spin Ice via Ultrafast Site-Specific Laser Annealing
• Realizing Blume-Capel Degrees of Freedom with Toroidal Moments in a Ruby Artificial Spin Ice