Ultrafast Polarization Control via All-Optical Modulation in Anisotropic Metasurfaces

Abstract

Sub-picosecond polarization control is a fundamental functionality for several applications, from information encoding to probing of chemical systems such as chiral molecules. We present an all-optically reconfigurable AlGaAs metasurface, showing giant dichroism modulation upon investigation via ultrafast pump-probe spectroscopy. By combining modelling of carriers excitation and relaxation processes with full-wave electromagnetic simulations, we can attribute the relevant transient features to pump-induced band-filling effect, opening a gain region in the spectral range of a sharp resonance of the structure. Show more