An Investigation On InGaAs/InAlAs Multiple Quantum Well Multi Mode Interference Optical Splitters/Couplers

As the basis of next generation optical network and the major platform of information transmission, Dense Wavelength Division Multiplexing optical network (DWDM-ON) has become the keystone of the development and construction of network. Optical splitters/couplers are the key devices for DWDM-ON, which can not only realize the allocations for optical power or signal as discrete devices, but also become the basic elements for other photonic devices, such as amplifier, signal monitor, optical switches, modulators and so on. This dissertation studies the InGaAs/InAlAs Multiple Quantum Well optical splitters/couplers based on multimode interference, including their theoretical analysis, optimal designs, and experiments.From Maxwell equations, the semi-vectorial models for analysis of the eigenvalue for optical rectangular waveguide, rib waveguide and coupled waveguide based on the Variable Transformed Galerkin Method (VTGM) has been presented and established. The distributions of electric field for eigen-mode and the effective index have been obtained. A novel three-dimensional semi-vectorial beam propagation method based on VTGM (3D-VTGM-SBPM) has been proposed and successfully applied to simulate directional coupler. Our results agreed good with those obtained by other methods, which assess the valid of the present method.Self Imaging Effect (SIE) is the primary principle for Multi-mode Interference (MMI) devices. The general and overlapping SIE have been elucidate in detail. Furthermore, the positions of input/output channel, the intensity as well as phase relative for the output images have been presented. In addition, the method for reducing the length of devices has been analyzed.At last, the novel 2(2 tunable and s-bent InGaAs/InAlAs MQW MMI-based optical splitters/couplers have been proposed and optimized using the SVTGM, 3D-SVTGM-BPM and FD-BPM. The optimal parameters have been given.