Electro-optic cofficient

r₃₃ (pronounced "r three three") also called the electro-optic coefficient is a measure of the changability optical activity of a material when an electric field is applied.

<math>r_{33} = \beta(\epsilon,\omega)N<cos^3\theta>\,\!</math>

where

<math>\beta(\epsilon,\omega)\,\!</math> is the molecular first hyperpolarizability which at a give wavelenth ω

<math>N\,\!</math> is chromophore number density

<math><cos^3\theta>\,\!</math> is the acentricity or order parameter

Figure-of-Merit

Figure-of-merit: r33 preferably > 1000 pm/V

Current Status: 600pm/V

For poled polymers for THz generation and detection

Figure-of-merit: r33 preferably > 350 pm/V

Current Status: 600pm/V

Measurement

Teng-Mann Method

Attenuated Total Reflectance