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Two-dimensional (2D) material–organic interfaces offer a platform to realize hybrid materials with tunable optical properties that are determined by the interactions between the disparate materials. This is particularly attractive for tailoring the optoelectronic properties of semiconducting monolayer transition metal dichalcogenides (TMDs). Here, we demonstrate evidence of coupled 2D semiconductor–molecular excitons with enhanced optical properties, which results from the atomically thin heterojunction. Specifically, we investigate the hybridization of the 2.16 eV WSe2B exciton with the 2.20 eV transition of perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA), observed by enhanced resonant Raman scattering by the PTCDA vibrational modes, with enhancements by a factor of nearly 20. The effect can be understood from a coupled oscillator model in which the strong absorption resonance of the WSe2monolayer increases the Raman scattering efficiency of the PTCDA. The Raman enhancement diminishes with increasing WSe2thickness, which is attributed to a reflectivity effect that reduces the intensity at the surface. The proposed hybridization effect may lead to new investigations into the nature of coupled excitons in atomically thin junctions.

For quantum technologies based on single excitons and spins, the deterministic placement and control of a single exciton is a longstanding goal. MoSe2-WSe2heterostructures host spatially indirect interlayer excitons (IXs) that exhibit highly tunable energies and unique spin-valley physics, making them promising candidates for quantum information processing. Previous IX trapping approaches involving moiré superlattices and nanopillars do not meet the quantum technology requirements of deterministic placement and energy tunability. Here, we use a nanopatterned graphene gate to create a sharply varying electric field in close proximity to a MoSe2-WSe2heterostructure. The dipole interaction between the IX and the electric field creates an ∼20 nm trap. The trapped IXs show the predicted electric-field-dependent energy, saturation at low excitation power, and increased lifetime, all signatures of strong spatial confinement. The demonstrated architecture is a crucial step toward the deterministic trapping of single IXs, which has broad applications to scalable quantum technologies.