Bulletin of the American Physical Society
APS March Meeting 2023
Volume 68, Number 3
Las Vegas, Nevada (March 5-10)
Virtual (March 20-22); Time Zone: Pacific Time
Session N50: Spin-wave transport, damping and interfacial effects for tailoring magnetization dynamicsInvited
|
Hide Abstracts |
Sponsoring Units: DCOMP Chair: Zhihao Jiang, University of Illinois at Urbana-Champaign Room: Room 320 |
Wednesday, March 8, 2023 11:30AM - 12:06PM |
N50.00001: From electronic structure to magnetisation dynamics Invited Speaker: Olle Eriksson In this talk, a computationally efficient scheme is outlined to evaluate all needed parameters to perform simulations of magnetization dynamics, both on an atomistic level as well as on a micromagnetic level. Examples of calculated Heisenberg exchange interaction, Dzyaloshinskii-Moriya (DM) interaction and the Gilbert damping parameter will be given. The accuracy of these parameters is addressed by calculating theoretical spin-wave spectra using them, and to compare these spectra to measured values. In the talk, possible microscopic mechanisms that determine the influence of these parameters will be discussed, involving non-collinear contributions to the DM interaction as well as mechanisms behind anisotropies of the Gilbert damping parameter. In addition, extension of atomistic spin-dynamics simulations to coupled spin-lattice dynamics will be presented, as well a multiscale method that connects an atomistic and micromagnetic description of the magnetization dynamics. These simulation tools open the door for a quantitative description and understanding of the microscopic origin of many fundamental phenomena of contemporary interest, such as ultrafast demagnetization and magnetocalorics, and results from such simulations will be presented. |
Wednesday, March 8, 2023 12:06PM - 12:42PM |
N50.00002: Non-local Gilbert damping and its influence on magnetisation dynamics Invited Speaker: Danny Thonig Gilbert damping is a key parameter in spintronics, which describes the rate of energy dissipation from the spin system to, e.g., phonons. Here, is typically considered as a scalar parameter in e.g., FMR experiments. However, there is recent experimental evidence that damping ij is a non-local [1], which is also discussed by theory [2-4]. This has consequences to the equation of motion for magnets. In this talk, we give an overview on properties of ij and the impact of it on magnetic observables. |
Wednesday, March 8, 2023 12:42PM - 1:18PM |
N50.00003: Giant Anisotropy of Gilbert Damping in Epitaxial CoFe Films Invited Speaker: Yi Li Tailoring Gilbert damping of metallic ferromagnetic thin films is one of the central interests in spintronics and spin-torque related applications. By investigating broadband spin-torque ferromagnetic resonance of Fe50Co50 and Fe50Co50/Pt, we observe as a function of magnetic field orientation a giant anisotropy of the Gilbert damping in epitaxial FeCo thin film with a maximum-minimum damping ratio up to 400%. The symmetry of damping follows the cubic magnetocrystalline anisotropy. In addition, we identify the origin of this damping anisotropy as the variation of spin-orbit coupling with magnetization orientations, which is reflected in the intensity of the rectification signals in FeCo as opposed to the density of state anisotropy. The damping anisotropy is compared with the angular dependence of the crystalline-induced anisotropic magnetoresistance, which was simultaneously obtained in the spin-torque resonance measurements. Our results provide new insights for the damping mechanism in metallic ferromagnets, which are important for optimizing dynamic properties of future magnetic devices. We will also discuss a few following up works that explores such an interesting anisotropy in CoFe films. |
Wednesday, March 8, 2023 1:18PM - 1:54PM |
N50.00004: Calculating spatially resolved (charge, spin and orbital) currents and what we can do with them Invited Speaker: Paul Kelly Phenomenological theories in spintronics are usually based upon semiclassical formulations of transport like the Boltzmann or diffusion equations that cannot easily accommodate the fundamentally quantum character of energy bands and Fermi surfaces; this is more readily done using scattering theory. The challenge for first-principles scattering theory is to describe the diffusive regime in which most experiments are performed. I sketch the developments that have allowed us to realize this goal culminating in the extraction of charge and spin currents [1] from large scale relativistic scattering calculations [2] that include temperature-induced lattice and spin disorder [3]. |
Wednesday, March 8, 2023 1:54PM - 2:30PM |
N50.00005: Probing Local Magnetization Dynamics and Static Interactions at Interfaces Invited Speaker: P Chris Hammel Interactions across magnetic/non-magnetic interfaces play a dominant role in spin based information manipulation and transport. High resolution spectroscopic measurement of static interfacial interactions and local characterization of magnetization dynamics provide important insight into the mechanisms underlying these phenomena. Here we discuss two high sensitivity magnetic resonance techniques that enable local measurement of these quantities. Scanned force magnetic resonance measurement of magnetic tip-localized spin wave modes allows spatially resolved measurement of both local magnetic dynamics and static interfacial interactions with Gauss-scale spectroscopic resolution. The photoluminescence of nitrogen-vacancy (NV) defects in diamond and boron-vacancy (BV) centers in hBN is sensitive to magnetic fluctuations generated by a nearby sample; this enables local measurement of magnetization dynamics. We close with illustrations of these approaches: scanned imaging of WTe2/YIG interfaces [1] and detection of AF resonance in CrCl3 [2]. |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700