Quasi-two-dimensional magnon identification in antiferromagnetic FePS3 via magneto-Raman spectroscopy

Published

February 18, 2020

Author(s)

Amber D. McCreary, Jeffrey R. Simpson, Thuc T. Mai, Robert D. McMichael, Jason E. Douglas, Nicholas P. Butch, Cindi L. Dennis, Rolando Valdes Aguilar, Angela R. Hight Walker

Abstract

Recently it was discovered that van der Waals-bonded magnets retain long range magnetic ordering even down to a monolayer thickness, opening many avenues in fundamental physics and potential applications of these fascinating materials. One example is FePS3, a high spin (S=2) Mott insulator shown to be a quasi-2D-Ising antiferromagnet in bulk, where new features in the Raman spectra emerge below the Neel temperature of approximately 120 K. Through magneto-Raman spectroscopy, we will show that one of these Raman-active modes in the magnetically ordered state previously referred to as a phonon is instead a magnon with a high frequency of 3.6 THz (121 cm-1). We observe the expected temperature dependence and splitting of the magnon under applied magnetic fields, determining the g-factor to be ≈2. In addition, the symmetry behavior of the magnon, which is not antisymmetric, is studied and explained using the magnetic point group of FePS3.

Citation

Physical Review B

Volume

101

Issue

6

Pub Type

Journals

Download Paper

https://doi.org/10.1103/PhysRevB.101.064416

Local Download

Keywords

Magnon, spin-wave, Raman spectroscopy, magneto-Raman, phonon, 2D materials, FePS3, Mott insulator

Citation

McCreary, A. , Simpson, J. , Mai, T. , McMichael, R. , Douglas, J. , , N. , Dennis, C. , Valdes, R. and Hight, A. (2020), Quasi-two-dimensional magnon identification in antiferromagnetic FePS3 via magneto-Raman spectroscopy, Physical Review B, [online], https://doi.org/10.1103/PhysRevB.101.064416 (Accessed October 8, 2025)