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

van der Waals MnPS₃ compound belonging to the class of Néel-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 Néel transition temperature (<i>T</i> _N = 78 K) for the magnetic field applied in the directions parallel and perpendicular to the crystallographic <i>c</i> axis. Furthermore, the ESR angular dependence at a temperature near <i>T</i> _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 <i>T</i> _BKT with <i>T</i> _BKT/<i>T</i> _N typically found in two-dimensional magnets.