Chiral switching and relaxation dynamics in artificial square ice

ORAL

Abstract

The relaxation kinetics and emerging correlations of arrays of interacting Ising-like nanomagnets are governed by the switching rates of the individual magnets. These rates depend, via the Arrhenius law, on the energy barrier for moment reversal in the nanomagnets. In this work, we consider how the switching behaviour of a nanomagnet in archetypical artificial square ice is modified by the interaction with its six nearest neighbours, and find that barrier energies for clockwise and counter-clockwise rotation can differ significantly. This effect is relevant for both exchange- as well as magnetostatically-dominated moment reversal. From string-method simulations we obtain further dynamical reductions of the switching barriers, as the micromagnetic structure evolves during reversal. The barrier splitting leads to an exponential enhancement of the transition rates compared to mean-field predictions. Finally, these modifications lead to faster relaxation dynamics and different spatial correlations in kinetic Monte Carlo simulations.

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Presenters

  • Naëmi Leo

    • CIC nanoGUNE, CIC nanoGUNE, San Sebastian, País Vasco, ES, other/research

Authors

  • Naëmi Leo

    • CIC nanoGUNE, CIC nanoGUNE, San Sebastian, País Vasco, ES, other/research

  • Sabri Koraltan

    • University of Vienna, Universitat Wien, Wien, Wien, AT, academic

  • Matteo Pancaldi

    • Stockholm University, Stockholms Universitet, Stockholm, SE, academic

  • Pedroáá Villalba González

    • CIC nanoGUNE, CIC nanoGUNE, San Sebastian, País Vasco, ES, other/research

  • Claas Abert

    • University of Vienna, Universitat Wien, Wien, Wien, AT, academic

  • Christoph Vogler

    • University of Vienna, Universitat Wien, Wien, Wien, AT, academic

  • Kevin Hofhuis

    • ETH Zürich, Eidgenossische Technische Hochschule Zurich, Zurich, ZH, CH, academic

  • Florian Slanovc

    • University of Vienna, Universitat Wien, Wien, Wien, AT, academic

  • Florian Bruckner

    • University of Vienna, Universitat Wien, Wien, Wien, AT, academic

  • Paul Heistracher

    • University of Vienna, Universitat Wien, Wien, Wien, AT, academic

  • Mattoe Menniti

    • CIC nanoGUNE, CIC nanoGUNE, San Sebastian, País Vasco, ES, other/research

  • Dieter Suess

    • University of Vienna, Universitat Wien, Wien, Wien, AT, academic

  • Paolo Vavassori

    • CIC nanoGUNE, CIC nanoGUNE, San Sebastian, País Vasco, ES, other/research