The Linear Electrooptic Effect

Nonlinear second order optical properties such as second harmonic generation and the linear electrooptic effect arise from the first non-linear term in the constitutive relation for the polarization P(t) of a medium in an applied electric field E(t) = E cos ot. 

Non-linear second-order optical properties such as second harmonic generation (SHG) and the linear electrooptic effect are due to the non-linear susceptibility in the relation between the polarization and the applied electric field. SHG involves the... 

There is great interest in preparing materials which could facilitate the development of electrooptic devices. Such devices could permit broad band optical signal encoding so that telephone, data, television, and even higher frequency transmissions could simultaneously be sent down a single optical fiber. The nonlinear optical process which makes this possible is the linear electrooptic effect (EO). It is based on the first field nonlinearities (Z ) of the molecular dipole moment, / ,... 

For the linear electrooptic effect (EO), the two-level model only differs in dispersion, with the dispersion factor, F q (co), given by... 

Figure 6.7. Upper linUts of x values reported for second harmonic generation of poled polymers, crystals, and LB films compared with those of inorganic crystals. Also noted is x /or the linear electrooptic effect in LiNbOa-...

Some of the relevant applications of nonlinear optics are currently used in laser technology and fiber communications, such as optical frequency conversion, optical parametric oscillation and amplification, the linear electrooptic effect (Pockels... 

The linear electrooptic effect is tlie change in the index of refraction of a medium due to the presence of a dc or low-frequency electric field, in such a manner that the change in the index of refraction depends linearly in the strength of the low-frequency electric field. The linear electrooptic effect is tlie mechanism behind optical intensity modulators that are used in optical switching and fiber-optics communications, where the optical signal is modulated at high frequencies (out to 110 GHz) [7-9],... 

The first observation of natural optical anisotropy was made in 1669 by Bartolinius in calcite crystals, in which light travels at different velocities depending on the direction of propagation relative to the crystal structure. The electrooptic effect, electric-field-induced anisotropy, was first observed in glass in 1875 by J. Kerr. Kerr found a nonlinear dependence of refractive index on applied electric field. The term Kerr effect is used to describe the quadratic electrooptic effect observed in isotropic materials. The linear electrooptic effect was first observed in quartz crystals in 1883 by W. Rontgen and A. Kundt. Pockels broadened the analysis of this relationship in quartz and other crystals, which led to the term Pockels effect to describe linear behavior. In the 1960s several developments... 

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