Low-Temperature Electron Spin Resonance Study of MnPS3 Antiferromagnetic Single Crystal

van der Waals MnPS3 compound belonging to the class of Neel-type antiferromagnets (AFM) has recently emerged as a promising two-dimensional material for spintronic applications. In this study, we report on the electron spin resonance (ESR) study of an MnPS3 single crystal across the Neel transition temperature (T N = 78 K) for the magnetic field applied in the directions parallel and perpendicular to the crystallographic c axis. Furthermore, the ESR angular dependence at a temperature near T N has been investigated. We observed multiple resonance modes with antiferromagnetic, ferromagnetic, and paramagnetic characters. In addition, we revealed the occurrence of complex spin-spin correlations and a magnetic-topological Berezinskii-Kosterlitz-Thouless (BKT) phase transition (i.e., bound vortex-antivortex pairs) at T BKT with T BKT/T N typically found in two-dimensional magnets.