Interlayer coupling in two-dimensional perovskite/monolayer transition metal dichalcogenides heterostructures

Abstract Two-dimensional (2D) materials have garnered significant attention due to their diverse compositions, pronounced excitonic effects and exceptional optoelectronic properties, providing a compelling platform for assembling the van der Waals heterostructures to explore novel physical phenomena and develop multifunctional applications. The highly tunable band structures of these materials allow for variable band alignments, facilitating detailed studies of charge and energy transfer processes, providing critical insights for the material selection, structural design, performance improvement and device optimization. In this perspective, we put emphasize on the van der Waals stacking of 2D perovskites and monolayer TMDs, specifically focusing the interlayer coupling in hybrid heterostructures exhibiting type II band alignments. We present a comprehensive review of the formation of interlayer excitons (IXs), supported by both theoretical calculations and experimental observations. The chemical tunability of the component layers enables robust and controllable IX characteristics over a broad spectral range, independent of stacking angles or lattice mismatch, and can be further manipulated by external fields, offering additional degrees of control. The unique coupled spin-valley physics of monolayer TMDs, combined with the and chiral-induced spin selectivity effects or Rashba splitting effects in 2D perovskites, can further introduce circular polarization to IXs. Finally, we conclude by outlining key challenges in advancing these material systems and understanding physical mechanisms, offering perspectives on future development for next-generation optoelectronic and valleytronic devices.