Low-Temperature\nElectron Spin Resonance Study of MnPS<sub>3</sub> Antiferromagnetic\nSingle Crystal

van der Waals MnPS<sub>3</sub> compound belonging to\nthe class\nof Néel-type antiferromagnets (AFM) has recently emerged as\na promising two-dimensional material for spintronic applications.\nIn this study, we report on the electron spin resonance (ESR) study\nof an MnPS<sub>3</sub> single crystal across the Néel transition\ntemperature (<i>T</i><sub>N</sub> = 78 K) for the magnetic\nfield applied in the directions parallel and perpendicular to the\ncrystallographic <i>c</i> axis. Furthermore, the ESR angular\ndependence at a temperature near <i>T</i><sub>N</sub> has\nbeen investigated. We observed multiple resonance modes with antiferromagnetic,\nferromagnetic, and paramagnetic characters. In addition, we revealed\nthe occurrence of complex spin–spin correlations and a magnetic-topological\nBerezinskii–Kosterlitz–Thouless (BKT) phase transition\n(i.e., bound vortex-antivortex pairs) at <i>T</i><sub>BKT</sub> with <i>T</i><sub>BKT</sub>/<i>T</i><sub>N</sub> typically found in two-dimensional magnets.