Dynamic Tuning of MoS₂ Photoluminescence via Thickness Modulation of CrSBr in van der Waals Heterostructures

Single-layer (1L) semiconducting transition metal dichalcogenides (TMDs) are known for their exceptional excitonic photoluminescence (PL), which can be enhanced through various methods such as defect engineering and environmental modifications. However, integrating TMDs into van der Waals heterostructures often results in a significant quenching of PL due to an increased rate of nonradiative recombination processes. In this study, we demonstrate an enhancement in the PL of 1L-MoS₂ when combined with the recently discovered magnetic semiconductor CrSBr. By examining the effect of CrSBr thickness on the PL of MoS₂, we discovered that CrSBr layers up to 18 nm thick enhance the PL of MoS₂, while thicker layers cause quenching. This behavior is potentially due to n- to p-type doping transition of MoS₂ upon contact with CrSBr. Additionally, we showcase the optoelectronic applications of this heterostructure, including photodetectors, memristors, and LEDs. These findings highlight a novel strategy for optimizing PL in TMDs through interlayer doping in van der Waals heterostructures.