What Is the Role of a Magnetic Mo Antisite Defect on Carrier Relaxation and Spin Dynamics in 2-D MoS2?

Antisite defects significantly influence the dynamic properties of monolayer MoS2, yet the carrier relaxation and spin dynamics in spin-polarized Mo antisite-defective MoS2 remain unclear. Understanding these processes is crucial for advancing optoelectronic, spintronic, and valleytronic devices. Here, we employ first-principles calculations and ab initio nonadiabatic molecular dynamics with spin-orbit coupling (SOC) to explore carrier relaxation and spin dynamics in MoS2 with a Mo antisite defect. This defect alters the material's magnetic properties, leading to distinct relaxation behaviors: electron relaxation is slower than hole relaxation, and charge carriers in different spin channels exhibit varied dynamics. These differences arise from variations in electron-phonon coupling, SOC strength, and phonon mode activation. Our findings provide key insights into charge and spin dynamics in MoS2 with magnetic defects and suggest strategies to enhance the performance of next-generation optoelectronic, spintronic, and valleytronic devices.