Matrix Order Influence on the Non‐Linear Optical Properties of Dispersed Chromophore‐Azopolymer Systems

Abstract

Azopolymers with moderate non‐linear optical (NLO) response are used as host matrices for a highly efficient molecule. The second harmonic intensity generated at room temperature by these binary systems increases noticeably by adding an irradiation step (406 nm) to the corona poling process. The free volume increase due to “trans‐cis” photoisomerization of the side‐chain azo moieties allows to align the NLO chromophores and causes, at least partially, this enhancement. In order to investigate the role of guest–host interactions on the NLO response, different matrix arrangements have been induced and different d33/d.

Methacrylic copolymers with quinoxaline chromophores in the side chain exhibiting quadratic nonlinear optical response

“…Two main synthetic routes have traditionally been employed for preparing side‐chain NLO polymers 3,5 . First, chromophore‐bearing monomers were synthesized and polymerized directly into homopolymers or copolymerized with an optically inert monomers 9–15 . Second, high molecular weight polymer precursors having reactive sites were prepared, and NLO chromophores were tethered through various postfunctionalization schemes 16–20 .…”

“…3,5 First, chromophore-bearing monomers were synthesized and polymerized directly into homopolymers or copolymerized with an optically inert monomers. [9][10][11][12][13][14][15] Second, high molecular weight polymer precursors having reactive sites were prepared, and NLO chromophores were tethered through various postfunctionalization schemes. [16][17][18][19][20] Although the degree of substitution may be hard to quantify, and reproducibility of the property may be compromised, the latter has often been adopted for a high yield of resultant NLO polymer.…”