Manipulation of Exciton Dynamics in Single-Layer WSe Using a Toroidal Dielectric Metasurface.

Recent advances in emerging atomically thin transition metal dichalcogenide semiconductors with strong light-matter interactions and tunable optical properties provide novel approaches for realizing new material functionalities. Coupling two-dimensional semiconductors with all-dielectric resonant nanostructures represents an especially attractive opportunity for manipulating optical properties in both the near-field and far-field regimes. Here, by integrating single-layer WSe and titanium oxide (TiO) dielectric metasurfaces with toroidal resonances, we realized robust exciton emission enhancement over 1 order of magnitude at both room and low temperatures.

[Evidence-based treatment of hemorrhoidal disease].

Hemorrhoidal disease represents a prevalent benign condition of the lower gastrointestinal tract. As a common and early symptom of hemorrhoids, patients present with painless rectal bleeding during or after defecation. For the treatment of hemorrhoidal disease, a large variety of operative and non-operative therapeutic options exists.