Enhancing and expanding the manipulated range of room-temperature valley polarization at off-resonance wavelength is extremely crucial to developing various functional valleytronic devices. Although these have been realized through the double-resonance strategy or twist-angle engineering, the demand for electrical control over the concepts remains elusive. Here, we fabricate a gate-tunable double-resonance chiral microstructure using a molybdenum disulfides (MoS2) monolayer. On the basis of the varied interface charge density, we demonstrate the huge photoluminescence (PL) tuning ability of this configuration. Furthermore, benefiting predominately from the screening of long-range e-h exchange interactions and the chiral Purcell effect, the electrical switching of the room-temperature valley polarization at off-resonance wavelength is also realized. Our work enriches the functions of TMDs-based optoelectronic devices and may create important applications in future valley-polarized encode and information processing devices.
Keywords: MoS2; chirality; double-resonance; photoluminescence; valley polarization.