Flexoelectrically Programmed Ferroelectric Domain Lattices Enable Deterministic Exciton Patterning in van der Waals Heterostructures

Abstract

Programmable spatial control of excitonic quasiparticles is essential for realizing integrated photonic and information‐encoding platforms based on van der Waals heterostructures. A common strategy is electrostatic gating, which switches ferroelectric polarization and modulates excitonic responses through carrier doping and field effects. However, electrically driven polarization control requires additional electrodes and repeated voltage cycling, which may introduce charge trapping, polarization fatigue, and long‐term reliability constraints, complicating device integration and scalability. Here, we demonstrate flexoelectrically assisted exciton patterning by integrating MoSe2/CuInP2S6 heterostructures onto periodic Au stripe arrays. Atomic force microscopy and Piezoresponse force microscopy reveal a periodic ferroelectric‐domain texture that closely follows the imposed surface Au stripe arrays corrugation. Meanwhile, a reduced‐order curvature‐based calculation analysis captures the periodic through‐thickness bending‐strain gradient and the associated flexoelectric polarization preference. The resulting ferroelectric landscape creates a domain‐dependent electrostatic environment in the adjacent MoSe2, producing a spatial redistribution of neutral exciton and trion emission together with modulation of their valley‐polarized response. By linking microscale deformation, flexoelectrically assisted ferroelectric‐domain patterning, and local excitonic behavior, this work establishes a scalable, fabrication‐defined route toward artificial excitonic lattices and spatially encoded optoelectronic architectures.