Coupling of excitons and electric polarization in a moiré TMD homobilayer

Transition metal dichalcogenide (TMD) moiré systems host a variety of strongly correlated electronic states and display novel light-matter interactions. TMD hetero- and homo-bilayers have distinct crystal symmetries, with homobilayers exhibiting higher symmetry at the expense of an indirect bandgap in most cases. However, twisted MoTe₂ (tMoTe₂) retains its direct bandgap and strong optical response. Using various optical probes, we show intertwined doping and electric field effects on excitons in tMoTe₂ arising from control over the layer symmetry. We also report on optical signatures of the crossover regime between the layer-degenerate and layer-polarized states of the system. This study establishes tMoTe₂ system as a promising system to explore excitonic physics within a highly tunable layer-degenerate moiré system.