Dielectric investigation of thermally-induced chromophore degradation in nonlinear optical polymer electrets

One of the critical issues with poled photonic polymers is the thermal stability of the nonlinear optical effect in these dipolar electrets. The temporal decrease of the nonlinear optical coefficients is caused by dipolar-relaxation and molecular-degradation processes. In this paper, it is demonstrated that dielectric measurements allow for an in-depth investigation of dipole-degradation processes in a typical side-chain photonic polymer. The results yield an estimate of effective device lifetimes, which are in some cases dominated by irreversible chemical degradation rather than by reversible dipolar relaxation.