Electro-optic measurement of Langmuir-Blodgett films layered with N-docosylquinolinium-TCNQ

Electro-optic coefficient, refractive index and dielectric dispersion for the Langmuir-Blodgett (LB) films of N-docosylquinolinium-TCNQ were obtained. The thickness of one layer of the LB film was 38.14Å at the surface pressure of 30mN/m, and the refractive index calculated from spectroscopic ellipsometry was 1.2∼1.3. The dielectric dispersion shows the frequency dependence of the orientational polarization and the resonance frequency, fr, was about 1.5kHz in the film. The electro-optic effect for the LB film were measured from the simple reflection technique. Suprisingly large electro-optic coefficient, 98.7∼69.3pm/V, were obtained.