Phonon and Thermal Properties of Quasi-Two-Dimensional FePS3 and MnPS3 Antiferromagnetic Semiconductor Materials

TL;DR

This study investigates the phonon and thermal properties of exfoliated FePS3 and MnPS3 antiferromagnetic semiconductors, revealing anisotropic thermal conductivities and new spectral features via resonant Raman spectroscopy, with implications for spintronic applications.

Contribution

It provides new insights into the phonon spectra and anisotropic thermal conductivities of FePS3 and MnPS3 thin films using advanced Raman and thermal measurement techniques.

Findings

Resonant UV-Raman spectroscopy detects new spectral features.

FePS3 has in-plane thermal conductivity of 2.7 W/mK.

MnPS3 exhibits higher thermal conductivities, with 6.3 W/mK in-plane.

Abstract

We report results of investigation of the phonon and thermal properties of the exfoliated films of layered single crystals of antiferromagnetic FePS3 and MnPS3 semiconductors. The Raman spectroscopy was conducted using three different excitation lasers with the wavelengths of 325 nm (UV), 488 nm (blue), and 633 nm (red). The resonant UV-Raman spectroscopy reveals new spectral features, which are not detectable via visible Raman light scattering. The thermal conductivity of FePS3 and MnPS3 thin films was measured by two different techniques: the steady-state Raman optothermal and transient time-resolved magneto-optical Kerr effect. The Raman optothermal measurements provided the orientation-average thermal conductivity of FePS3 to be 1.35 W/mK at room temperature. The transient measurements revealed that the through-plane and in-plane thermal conductivity of FePS3 is 0.85 W/mK and 2.7 W/mK, respectively. The films of MnPS3 have higher thermal conductivity of 1.1 W/mK through-plane and 6.3 W/mK in-plane. The data obtained by both techniques reveal strong thermal anisotropy of the films and the dominant contribution of phonons to heat conduction. Our results are important for the proposed applications of the antiferromagnetic semiconductor thin films in spintronic devices.