Characterization of coplanar poled electro optic polymer films for Si-photonic devices with multiphoton microscopy

We imaged coplanar poled electro optic (EO) polymer films on transparent substrates with a multiple-photon microscope in reflection and correlated the second-harmonic light intensity with the results of Pockels coefficient (r33) measurements. This allowed us to make quantitative measurements of poled polymer films on non-transparent substrates like silicon, which are not accessible with traditional Pockels coefficient measurement techniques. Phase modulators consisting of silicon waveguide devices with EO polymer claddings with a known Pockels coefficient (from Vπ measurements) were used to validate the correlation between the second-harmonic signal and r33. This also allowed us to locally map the r33 coefficient in the poled area.