DESIGN AND MODELING OF APPLICATION SPECIFIC OPTICAL WAVEGUIDES

Abstract

Integrated-optic waveguide lasers have been a matter of considerable attention for research because of their unique features, such as compactness and possibility of integrating single mode waveguide are usually employed in such lasers to avoid mode competition and intermodal dispersion. Hence, in this report a multi-trench leaky channel waveguide design is presented that supports an effective single guided mode. The waveguide works on the principle of higher-order mode discrimination. The structure is analysed by the finiteelement method and the leakage loss of the modes along with the effective mode area have been calculated. It is shown that waveguide formed in silica with core width of 4 μm can exhibit single mode operation at 1550 nm wavelength. Numerical results show that wavelength ensure extended single mode operation in the wavelength range of 1.25-2.0 μm with a rectangular core area as large as 50 μm2. A theoretical investigation of a promising design of highly nonlinear As2Se3 based Chalcogenide waveguide is reported for generation of tunable slow light and its application at 1550 nm. The effective mode area and the confinement loss have been observed by varying the half width and height of the core of waveguide. Hence, the maximum allowable pump power for undistorted output pulse and time-delay experienced by the pulse propagating in designed waveguide are simulated. It has been observed that, in a 10 cm long Chalcogenide (As2Se3), the time-delay of ~252 ns can be obtained, when pumped with a peak power of 588 mW. Simulated results indicate that the timedelay experienced by the pulse can be tuned with the pump power and structural parameter of As2Se3 Rib Waveguide.