Recently, the determination of the topological Hall effect has caused some controversy in the field of spintronics due to the validity of subtracting a magnetization-scaled anomalous Hall component from an experimentally measured Hall resistance. Often the underlying magnetic texture and topology are determined ex-situ of the Hall measurement which can lead to experimental error. Here we report the simultaneous determination of the magnetic texture and Hall effect in a ferrimagnetic FeGd thin film using resonant soft X-ray scattering with in-situ magneto-electrical transport. We find the largest departure of the Hall component at the 6-fold symmetric scattering of the dipole skyrmion state but also an additional smaller feature of opposite sign at higher fields where we observe diffuse scattering just before saturation. We attribute this additional feature to a skew scattering term arising from isolated skyrmions close to saturation.
We report studies of spin textures including domain walls and skyrmions in synthetic antiferromagnetic multilayers. We have observed: phase coexistence of uniform antiferromagnetic regions with textured ferromagnetic regions during magnetisation; current-driven domain wall motion at lower current densities than in comparable ferromagnetic multilayers; and current-driven nucleation of a synthetic antiferromagnetic skyrmion.
Sophie Morley, Aaron Stein, Mark Rosamond, Diego Alba Venero, Aleš Hrabec, Philippa Shepley, Mi-Young Im, Peter Fischer, Matthew Bryan, Dan Allwood, Paul Steadman, Sean Langridge, Christopher Marrows
Artificial spin ices are often spoken of as being realisations of some of the celebrated vertex models of statistical mechanics, where the exact microstate of the system can be imaged using advanced magnetic microscopy methods. The fact that a stable image can be formed means that the system is in fact athermal and not undergoing the usual finite-temperature fluctuations of a statistical mechanical system. In this paper we report on the preparation of artificial spin ices with islands that are thermally fluctuating due to their very small size. The relaxation rate of these islands was determined using variable frequency focused magneto-optic Kerr measurements. We performed magnetic imaging of artificial spin ice under varied temperature and magnetic field using X-ray transmission microscopy which uses X-ray magnetic circular dichroism to generate magnetic contrast. We have developed an on-membrane heater in order to apply temperatures in excess of 700 K and have shown increased dynamics due to higher temperature. Due to the ‘photon-in, photon-out' method employed here, it is the first report where it is possible to image the microstates of an ASI system under the simultaneous application of temperature and magnetic field, enabling the determination of relaxation rates, coercivties, and the analysis of vertex population during reversal.
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.