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We propose two novel electro-optic (EO) deflectors based on two new nonrectangular geometries: the parabolic and the half-horn configurations. These devices not only provide excellent deflection angles, but also have the potential to build nonblocking 2 x 2 optical switches. A deflector figure of merit is defined, and comparisons with existing EO deflectors are given. Devices fabricated in LiTaO(3) demonstrate 3 dB of average insertion loss and 3 degrees deflection angles. These results represent the best deflection performances to our knowledge reported to date for bulk EO deflectors.

We investigate lattice orientation and strain fields across ferroelectric domain walls in a single crystal lithium tantalate using x-ray diffraction imaging ͑topography͒. The sample is an actual voltage-operated optical switch consisting of a series of triangular polarization-inverted domains formed in an originally poled single crystal. By applying an electric field only about 2% of the coercive field in the forward and reverse directions, we observed asymmetric lattice rotation of about 10 −6 rad, and normal strain variation in the order of 10 −5 with reference to the zero-field state. Our results confirm that in congruent LiTaO 3 crystals there is unexpectedly large strain field expanding several micrometers across the domain walls, in contrast with the widely accepted theoretical fact that in this material the polarization reversal establishes over only a few lattice constants, resulting in small and localized lattice distortions.

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