Polarization-resolved cubic nonlinearity and optical power limiting of highly porous silica nanoaerogels

A highly porous silica nanoaerogel has a strong optical power limiting behavior with a negative nonlinear property. The third-order nonlinear susceptibility of silica nanoaerogels was estimated to be ~9.6 x 10
^-19
m
²
/ V
²
(~6.9 x 10
^-11
esu) from DFWM measurements.