An electrostatically self-assembled monolayer, composed of a pair of layers of anionic molecules and cationic polymers with a hemicyanine pendent group, was fabricated onto a thin silver film. By use of the attenuated total internal reflection technique, surface plasmon resonance and reflection modulation spectra were measured to determine the electro-optic coefficients of the monolayer. In order to take into account the dielectric property of each layer, a five-layer model is adopted in obtaining the electro-optic coefficients. From the temperature dependence measurement of reflection modulation signal, the hyperpolarizabilities of the hemicyanine pendent chromophore in benzenoid and quinoid forms are obtained.
Bibliographical noteFunding Information:
This work was supported by the Korea Science and Engineering Foundation through the Quantum Photonic Science Research Center at Hanyang University.
- Electro-optic effect
- Self-assembled monolayer