Improving the thermal stability by anchoring both ends of chromophores in the side-chain nonlinear optical polymers

Abstract

We report our study of a new side‐chain second‐order nonlinear optical polymer in which both ends of the chromophores are anchored by thermal crosslinking during electric field poling. A sizable second‐harmonic generation coefficient d₃₃ of 60 pm/V was measured at 1064 nm fundamental wavelength with corona poling. After anchoring both ends of the chromophores, the thermal stability of the poling alignment was greatly improved and the nonlinear optical properties were shown to be stable at both 90 and 125 °C. Channel waveguides were defined in the polymer thin films by reactive ion etching.