Electrical manipulation of inter-valley trions in twisted MoSe₂ homobilayers at room temperature

The impressive physics and applications of intra- and interlayer excitons in a transition metal dichalcogenide twisted-bilayer make these systems compelling platforms for exploring the manipulation of their optoelectronic properties through electrical fields. This work studies the electrical control of excitons in twisted MoSe₂ homobilayer devices at room temperature. Gate-dependent micro-photoluminescence spectroscopy reveals an energy tunability of several meVs originating from the emission of excitonic complexes. Furthermore, it investigates the twist-angle dependence of valley properties by fabricating devices with distinct stacking angles. Strengthened by density functional theory calculations, the results suggest that, depending on the rotation angle, the conduction band minima and hybridized states at the Q-point promote the formation of inter-valley trions involving the Q-and K-points in the conduction band and the K-point in the valence band. Besides exploring the charge-carrier manipulation in twisted homobilayers, our findings open new avenues for engineering multifunctional optoelectronic devices based on ultrathin semiconducting systems.