Tunable LiNbO3-Based Diffraction Optical Elements for Control of Coherent Light

Ferroelectric domains have been used extensively over the past years for nonlinear optical applications. Quasi-phase-matched frequency conversion processes such as second harmonic generation, optical parametric generation and oscillation can be realized using the periodically poled ferroelectric domain structures in LiNbO
₃
(LN) and LiTaO
₃
single crystals. These quasi-phase-matching process in this case is based on the opposite values of second order susceptibility tensors in neighboring domains. On the other hand, the ferroelectric domains with opposite values of spontaneous polarization possess also the opposite values of the linear electrooptic effect, which allowed to demonstrate the electrical field controlled optical beam deflectors [1-3], diffusers [4], Fresnel zone plates [5] and more sophisticated Shack-Hartmann sensors [6].