Second harmonic generation from exciton-magnons in van der Waals antiferromagnet MnPS₃

Antiferromagnets comprise an important platform for spintronics due to their ultrafast spin dynamics. Recent discovery of two-dimensional (2D) van der Waals (vdW) antiferromagnets with strong intralayer charge-spin correlations has further sparked great interest in ultrafast opto-spintronics. The magnon-sideband of exciton, so-called exciton-magnons, has been observed in the optical absorption spectra of Néel-type vdW antiferromagnet MnPS₃ [1]. Nevertheless, its origin and dynamics are far from being well understood. We will present our nonlinear optical spectroscopic characterization of exciton-magnons in MnPS₃, focusing on its electronic/magnetic symmetry, and discuss their potential use in ultrafast photogeneration of magnons.

[1] S. Gnatchenko et al. Low Temp. Phys. 37, 144-148 (2011)