Investigating ferromagnetic response in monolayer CVD grown MoS2 flakes using quantum weak measurement

We synthesize MoS2 atomic layer flakes at different growth conditions to tailor S-terminated and Mo-terminated edge defect states that are investigated for their ferromagnetic response. We leverage quantum weak measurement principles to construct a spin Hall effect of light-based magneto-optic Kerr effect (SHEL-MOKE) setup to sense the ultra-small magnetic response from the synthesized atomic layers. We establish that Mo-terminated edge states are the primary source of ferromagnetic response from MoS2 flakes, which is consistent with x-ray photoelectron, Raman, and photoluminescence spectroscopic results. In the process, we demonstrate SHEL-MOKE to be a robust technique to investigate ultra-weak magnetic properties in novel atomic-scale materials. Our findings highlight the importance of controlling edge terminations in engineering magnetism at the nanoscale and underscore the potential of weak value amplification based optical measurements.