Engineering, Tuning, and Trapping Excitons in Ferroelectric R‑WSe₂

Transition metal dichalcogenides with rhombohedral (3R) stacking order are excellent platforms to realize multiferroelectricity. Here we investigate both intralayer and interlayer excitons in artificially R-stacked bilayer WSe₂, which forms ferroelectric domains due to relaxation and stress. Via optical spectroscopy as a function of doping and external electric fields at cryogenic temperature, we explore the profound effect of ferroelectric domains—with built-in polarization—and the highly tunable band structures on the exciton and exciton-polaron (trion) behaviour.



We further reveal that ferroelectric domain intersections act as natural nanoscale potential minima that spatially confine interlayer excitons, giving rise to discrete, quantum-dot-like emission lines with narrow linewidths. These quantum emitters emerge from the interplay between local electrostatic fields, strain gradients, and polarization discontinuities at domain boundaries. Remarkably, owing to sliding ferroelectricity, the position of these emitters can be electro-mechanically reconfigured, enabling dynamic control of their spatial location and emission properties.



This work highlights the interplay between band structure tuning and ferroelectric domain behaviour and lays a foundation for future applications in 2D device engineering and reconfigurable quantum optoelectronics.