The MagLab is funded by the National Science Foundation and the State of Florida.
The MagLab is funded by the National Science Foundation and the State of Florida.
Title: Raman spectroscopy of 2D magnets
Series: Condensed Matter Sciences Seminar
Host: Naipeng Zhang
Abstract: Van der Waals (2D) materials with intrinsic magnetism have attracted massive interest because of their potential applications in data storage and spintronics devices. Atomic layers of chromium triiodide (CrI3) are one of such 2D ferromagnetic (FM) materials that have been demonstrated to realize long range FM order in its monolayer limit. Raman spectroscopy is a convenient and powerful technique to probe the lattice, electronic, and magnetic excitations in 2D magnets. In this talk, I will present our Raman spectroscopy studies of magnons (spin waves) in bulk CrI3 and studies of moiré magnetism in twisted double bilayer CrI3. We have revealed a novel mixed state of layered antiferromagnetism (AFM) and FM in 3D bulk CrI3 and have revealed the emergence of finite net magnetization that originates from spin frustrations and noncollinear spin texture introduced by moiré superstructures in twisted double bilayer CrI3. I will also show our Raman spectroscopy studies of spin-induced nematicity in few-layer XY-type magnet NiPS3 and our observation of phonon Zeeman splitting in monolayer MoS2 which is usually considered as a non-magnetic material. Our Raman spectroscopy studies offer an unprecedented venue for probing novel magnetic states and phases in 2D magnets.