Raman spectroscopy of atomically thin two-dimensional magnetic iron phosphorus trisulfide (FePS3) crystals

Metal phosphorous trichalcogenide is an important group of layered two-dimensional (2D) materials with potentially diverse applications in low-dimensional magnetic and spintronic devices. Herein we present a comprehensive investigation on the lattice dynamics and spin-phonon interactions of mechanically exfoliated atomically thin 2D magnetic material-iron phosphorus trisulfide (FePS3) by Raman spectroscopy and first principle calculations. Layer-number and temperature dependent Raman spectroscopy suggests a magnetic persistence in FePS3 even down to monolayer regime through the spin-phonon coupling, while the Neel temperature decreases from 117 Kin bulk to 104 K in monolayer sample. Our studies advocate the intriguing magnetic properties in 2D crystals and suggest that FePS3 is a promising candidate material for future magnetic applications.