Figure 4 : Demonstration of PA reduction via grating coupling.

From: Luminescent hyperbolic metasurfaces

Figure 4

(a) LuHMS with wavelength-scale grating coupler fabricated with focused ion beam milling. The grating is designed to improve, both in-coupling of the pump and out-coupling of emission polarized normal to the metacrystal Bloch vector, KB. Comparison of (b) Pump PA and (c) DOLP in the absence and presence of gratings. Improved coupling of normal-polarized light reduces the pump PA and DOLP, consistent with behaviour of simulated LuHMS. The reduction in anisotropy occurs across all measured grating periods and is robust to small changes in geometric parameters of the LuHMS (see Supplementary Fig. 10 and Supplementary Note 6).