Large refractive index change in silicone-based and non-silicone-based hydrogel polymers induced by femtosecond laser micro-machining.
A Ti:Sapphire femtosecond laser with a pulse energy of 1.3 nJ at a 93 MHz repetition rate has been used to micro-machine optical gratings inside several silicone-based and non-silicone-based hydrogel polymers. By measuring the diffraction efficiency of the gratings at 632.8 nm, we find as large as 0.06+/- 0.005 average refractive index change within the irradiated area.
Ding
Li
L
Blackwell
Richard
R
Kunzler
Jay F
JF
Knox
Wayne H
WH