Artificial spin ices are arrays of correlated nano-scale magnetic islands that prove an excellent playground in which to study critical phenomena. In this contribution, we discuss how both geometry and the coupling of islands to external fields influence magnetic order. Using Lorentz transmission electron microscopy, we study a transition between antiferromagnetic and ferromagnetic order across a continuum of spin ice geometries. We show how emergent anisotropies can arise in field-driven processes and how relaxation timescales can be adjusted locally within arrays through a coupling to a site-specific bias field. Our work demonstrates artificial spin ice as an excellent testbed in which to probe non-equilibrium phenomena in low-dimensional systems.
Manipulation of magnetic chirality is of outermost importance due to the great technological and scientific opportunities it unlocks. Over the last decade, this manipulation has been achieved through the harnessing of chiral spin interactions in non-centrosymmetric materials and thin film interfaces (DMI), allowing for the creation and tuning of topologically non-trivial chiral spin textures such as spin-spirals and Skyrmions, of great scientific and technological interest. Here we will discuss how state of the art 3D nano-printing can be employed to create 3D geometries that host complex chiral spin textures and how such geometries can be combined to create artificial interfaces where spin textures of different chirality are forced to match each other [1]. Characterization of the resulting spin states using magnetic X-ray microscopy will be presented.
[1] Sanz-Hernández, D., et al. arXiv:2001.07130 [cond-mat.mes-hall]
Sub-100-nm skyrmions are stabilized in magnetic metallic multilayers and observed using transmission electron microscopy, magnetic force microscopy, scanning transmission X-ray microscopy and X-ray resonant magnetic scattering. All these advanced imaging techniques demonstrate the presence of 'pure' Neel skyrmion textures with a determined chirality. Combining these observations with electrical measurements allows us to demonstrate reproducible skyrmion nucleation using current pulses, and measure their contribution to the transverse resistivity to detect them electrically. Once nucleated, skyrmions can be moved using charge currents. We find predominantly a creep-like regime, characterized by disordered skyrmion motion, as observed by atomic force microscopy and scanning transmission X-ray microscopy. These observations are explained qualitatively and to some extent quantitatively by the presence of crystalline grains of about 20nm lateral size with a distribution of magnetic properties.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.