Laser-induced hole coherence in 2D antiferromagnet MPS 3 through spatial self-phase modulation

Transition metal phosphorus sulfides (MPS 3 ), a family of two-dimensional magnetic materials with a van der Waals structure, exhibit promising applications in nonlinear optical devices. The emergence of carrier coherence in MPS 3 is a fascinating topic in coherently controlling the nonlinear effect (or other novel phenomena). Herein, we systematically investigated the third-order nonlinear optical responses of MPS 3 (M = Ni, Fe, Mn) flake suspensions based on spatial self-phase modulation (SSPM) effect. The effective monolayer third-order nonlinear susceptibilities ( χ monolayer (3) ) of NiPS 3 and MnPS 3 are obtained for the first time at multiple wavelengths. Our results show that NiPS 3 has a higher χ monolayer (3) value (3.59 × 10 −9 e.s.u. or 5.01 × 10 −17 m 2 V -2 at 405 nm excitation) than those of FePS 3 and MnPS 3 . Furthermore, we laser-induced non-local hole coherence in MPS 3 based on SSPM, where the origin of excited-state holes is analyzed from electronic structures. The relationships between hole mobility μ hole , effective mass m h ∗ , and χ monolayer (3) for the three materials fulfill the previous investigation results. Because laser-induced hole coherence has rarely been reported, our investigation enriches the coherent regulation of two-dimensional magnetic MPS 3 materials, enabling potential applications in all-optical devices.