Seminarium Fizyki Ciała Stałego
sala 0.06, ul. Pasteura 5
2026-10-16 (10:15) 
dr Helgi Sigurðsson (Institute of Experimental Physic, Faculty of Physics, University of Warsaw)
"Topological Jackiw-Rebbi states in photonic van der Waals heterostructures"
Topological photonic systems offer robust light confinementand controlled transport, with promising applications in nanophotonics,localization, and lasing. Meanwhile, van der Waals (vdW) materialsprovide unique optoelectronic properties and intrinsic adhesion todiverse substrates, enabling complex multilayer architectures. I willtalk about our recent work on one-dimensional topological photonicplatform based on stacked nanostructured and planar layers of quasi-bulkWS₂. By engineering two topologically distinct gratings, we realizeJackiw-Rebbi interface states operating in the near-infrared spectralregion around 750 nm. These states are characterized through far-fieldoptical measurements, exhibiting linewidths of approximately 10 meV,highly directional emission, and narrow angular bandwidth. Scanningnear-field optical microscopy further reveals strong spatial confinementof the Jackiw-Rebbi mode at the interface between the gratings. Todemonstrate the potential of these states for controlling lightemission, we incorporate monolayer WSe₂ into a five-layer vdW gratingheterostructure and couple its photoluminescence to the topologicalinterface state. This interaction produces directional enhancement ofexcitonic emission by up to 22-fold compared with an uncoupledmonolayer. Our results offer fresh perspectives on vdW-based topologicalphotonic heterostructures as a versatile platform for robust lightlocalization, directional emission, and enhanced light-matterinteractions.