Fig. 1: Upconversion emission enhancement with polarization control.

A 980 nm laser beam is directed into a non-rotationally symmetric arrangement of nanobricks comprising an all-dielectric metasurface. Through the interplay of QBIC resonance (green pattern) and Mie resonance effects (red pattern), upconversion nanoparticles (pink spots) coated onto the surface of the nanobricks exhibit enhanced fluorescence emission with directional polarization controls