
Trends in Magnetism Online Seminar
February 27 @ 14:00 - 15:00
Title: Probing ultrafast dynamics in magnetic materials by pump probe spectroscopy
Speaker: Dr. Lakshmi Das — Ultrafast Nanoscience, Department of Physics, Umeå University, Sweden
Where: Zoom (Meeting ID: 617 3126 3754, Passcode: 490241)
Abstract:
My research employs ultrafast pump-probe spectroscopy to investigate the charge and spin dynamics of antiferromagnetic (AFM) materials on femtosecond timescales. In this study, I focus on time-resolved changes in reflectivity, transmission, and magneto-optical phenomena, such as the Magneto-Optical Kerr Effect (MOKE) and the Voigt effect, in AFM systems. The goal of my work is to deepen our understanding of ultrafast magnetization dynamics in AFM materials, where the antiparallel alignment of spins results in zero net magnetization, presenting unique challenges compared to traditional ferromagnetic (FM) materials. Additionally, the higher magnon precession frequencies in AFMs (on the order of THz) make them ideal candidates for ultrafast spin control, which has significant implications for the development of next-generation spintronic and quantum devices.
In this talk, I will provide an overview of ultrafast pump-probe measurements conducted on various AFM materials of interest, which are explored in the Ultrafast Nanoscience group at Umeå. I will also introduce my upcoming Marie Sklodowska-Curie postdoctoral project, ATOPS (Ultrafast Optical Antiferromagnetic Topological Spintronics), set to begin in the summer of 2025.