A detailed investigation of surface acoustic wave (SAW) propagating in x-cut y propagation lithium niobate (LiNbO3) for integrated acousto-optic tunable filters (IAOTF) is reported in this paper. With getting curves of velocities, the walk-off angular (the angular between the power-flux vector and the propagation direction) can be obtained by the cubic spline interpolation method. The electromechanical coupling constant curve is given. Now, an optimal configuration of IAOTF has been designed, in which the direction of interdigital transducer should be inclined about 4.18°.
Based on the coupled-mode theory, Cherenkov second harmonic generation (CSHG) from a channel waveguide has been analyzed and discussed in detail. The conversion efficiency with only conversion depletion and the conversion efficiency with conversion depletion and propagation loss are obtained respectively, the results show that for the case of low conversion efficiency the conversion depletion can be neglected, but for the case of high conversion efficiency we must take conversion depletion into account, and the propagation loss must be taken into accounted for the both. Furthermore, the nonlinear phase shift (NPS) of the fundamental beam can be maximized by choosing appropriate grating period and appropriate waveguide thickness, which makes the configuration have a promising potential to realize all-optical switches.
Surface Acoustic Waves (SAW) propagating in a semi-infinite, anisotropic medium Lithium niobate(LiNbO3) are discussed. Integrated Acousto-Optical Tunable Filters (AOTF) have demonstrated wide application in various fields of laser technology, spectroscopy, optoelectronics and optical signal processing as well as wavelength division multiplexed (WDM) networks. We fabricated practical quasi-collinear integrated AOTF.
In an earlier approach, the 2-D acoustical field profiles on the substrate region are often calculated with BPM. In this
paper, we present a new approach based on the finite element - artificial transmitting boundary method and calculate the
2-D acoustical field on the substrate region.