Magnetic skyrmion interactions in the micromagnetic framework
Physical Review B: Condensed Matter and Materials Physics American Physical Society 101:13 (2020) 134422
Abstract:
Magnetic skyrmions are localized swirls of magnetization with a nontrivial topological winding number. This winding increases their robustness to superparamagnetism and gives rise to a myriad of novel dynamical properties, making them attractive as next-generation information carriers. Recently the equation of motion for a skyrmion was derived using the approach pioneered by Thiele, allowing for macroscopic skyrmion systems to be modeled efficiently. This powerful technique suffers from the prerequisite that one must have a priori knowledge of the functional form of the interaction between a skyrmion and all other magnetic structures in its environment. Here we attempt to alleviate this problem by providing a simple analytic expression that can generate arbitrary repulsive interaction potentials from the micromagnetic Hamiltonian, using it to provide a correction to the interaction between a skyrmion and the boundary of its material. We also discuss a toy model of the radial profile of a skyrmion, which is accurate for a wide range of material parameters.Element- and Time-Resolved Measurements of Spin Dynamics Using X-ray Detected Ferromagnetic Resonance
Synchrotron Radiation News Informa UK Limited 33:2 (2020) 12-19
Element- and time-resolved measurements of spin dynamics using x-ray detected ferromagnetic resonance
Synchrotron Radiation News Taylor and Francis 33:2 (2020) 12-19
Abstract:
The technique of x-ray detected ferromagnetic resonance (XFMR) represents an indispensable new tool in the investigation of spin current effects in complex heterostructures, as it enables the observation of magnetization and spin dynamics with element-, site-, and valence state-specificity. Here we give an overview of the development of XFMR and characterize different approaches to measure spin dynamics using synchrotron radiation. We provide a detailed description of the working principle of the technique and give an overview of recent work carried out at beamline 4.0.2 of the Advanced Light Source and beamline I10 of the Diamond Light Source using XFMR. Results from our latest publications demonstrate the capabilities and sensitivity of the technique. Element- and phase-resolution provide intriguing insights into the mechanisms of spin current propagation in multilayers, while the high sensitivity of XFMR allows for detection of even miniscule signals. Most recently, the utilization of linearly polarized x-rays for XFMR and the detection of XFMR by means of x-ray diffraction rather than x-ray absorption demonstrate two new capabilities in the investigation of spin dynamics.Proximity-Induced Odd-Frequency Superconductivity in a Topological Insulator
(2020)
Tailoring Hybrid Anomalous Hall Response in Engineered Magnetic Topological Insulator Heterostructures
Nano Letters: a journal dedicated to nanoscience and nanotechnology American Chemical Society (2020)