Figure 1
From: All-optical dynamic focusing of light via coherent absorption in a plasmonic metasurface
Dynamic optical focusing with a metasurface absorber of substantially sub-wavelength thickness. (a) A focused signal beam A produces focal spot 1. A coherent structured control beam B modifies signal beam A by controlling absorption on a metasurface absorber, producing (b) a modified focal spot 2 or (c) eliminating the focal spot altogether.
