Extreme Concentration and Nanoscale Interaction of Light

Abstract

Concentrating light strongly calls for appropriate polarization patterns of the focused light beam and for up to a full 4π solid angle geometry. Focusing on the extreme requires efficient coupling to nanostructures of one kind or another via cylindrical vector beams having such patterns, the details of which depend on the geometry and property of the respective nanostructure. Cylindrical vector beams can not only be used to study a nanostructure, but also vice versa. Closely related is the discussion of topics such as the ultimate diffraction limit, a resonant field enhancement near nanoscopic absorbers, as well as speculations about nonresonant field enhancement, which, if it exists, might be relevant to pair production in vacuum. These cases do require further rigorous simulations and more decisive experiments. While there is a wide diversity of scenarios, there are also conceptually very different models offering helpful intuitive pictures despite this diversity.

On-axis complex-amplitude modulation for the generation of super-stable vector modes

“…From a fundamental point of view, vector beams have gained popularity as classical analogous of quantumentangled states, due to the mathematical similarity in which both are expressed [4,5]. From the applied side, vector beams are paving the way for applications in fields as diverse as optical communications, optical tweezers, and optical metrology, to name a few [6][7][8][9][10][11][12][13].…”