Spontaneous Domain Wall Fluctuation in Artificial Square Spin Ice Studied with Soft X-Ray Photon Correlation Spectroscopy

ORAL

Abstract

Artificial spin ice (ASI) systems, initially introduced to model spin ice systems in nature, are 2D array of frustrated dipolar-coupled nanomagnets. We performed soft x-ray photon correlation spectroscopy (XPCS) on the antiferromagnetic Bragg peak of thermally active square ASI and studied its domain wall dynamics as functions of temperature. Our result shows seconds-to-milliseconds timescale nucleation and annihilation of a single domain wall in the region under-study. We calculated the respective autocorrelation functions of domain fluctuation, whose characteristic curvatures indicates the distinct fluctuation time scale of the ASI systems that are coupled through dipole interaction.

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Presenters

  • Jeffrey Hastings

    University of Kentucky, Electrical and Computer Engineering, University of Kentucky

Authors

  • Xiaoqian Chen

    University of Kentucky and Lawrence Berkeley National Laboratory

  • James Lee

    ALS, Lawrence Berkeley National Laboratory

  • Sujoy Roy

    Lawrence Berkeley National Laboratory, ALS, Lawrence Berkeley National Laboratory, Advanced Light Source, Lawrence Berkeley National Laboratory

  • Barry Farmer

    Physics, University of Kentucky

  • Justin Woods

    University of Kentucky, Physics, University of Kentucky

  • Lance De Long

    Physics, University of Kentucky

  • Jeffrey Hastings

    University of Kentucky, Electrical and Computer Engineering, University of Kentucky