A Low Loss And Low Power Digital Thermo Optical Switch Based On Silicon Waveguide

In today's information age,Optical Switches,as the core control part of optical information exchange in All Optical Network(AON),have been widely concerned.Among them,silicon waveguide switching devices based on Planar Lightwave Circuits(PLC)technology have presented extensive application prospects and huge market potential due to their advantages in device integration and technique compatibility with the modern industrial infrastructure.In this paper,on silicon-on-insulator(SOI)waveguide platform,a regime of low-loss low-power digital thermo-optical(TO)switches of the reflected guided-mode is studied.Enhanced by a Bi-waveguide Corner Mirror(B-WCM)structure,a regime of the digital TO switches is proposed with an effective combination of three physical effects:Goos-H(?)nchen Shift(GH),Imbert-Fedorov(IF)Shift and refractive index TO modulation(RIM)effect of a reflected guided-mode.Through the theoretical modeling and data calculations,the correlation between the IF and GH Shifts,and the performance dependences of the digital TO switches on these effects are established.The finite difference time domain(FDTD)software produced by Optiwave Corp is employed to simulate performance of the SOI waveguide b-WCM type digital TO switches.When the refractive index and the thickness of both the SiO₂ insulating and upper cladding layers are 1.444 and 2.0?m,respectively,the refractive index of core Si material is 3.46,the heights of the inner and outer ridge are0.5?m and 1.5?m,respectively,and the width of ridge is 4.0?m,the effective refractive indices of guided modes E_x(TE)and E_y(TM)are 2.9?3.2.As result,when the refractive index of corner mirror Si₃N₄ material is 2.0,the device can realize the three optimal power outputs of 0.185028,0.892413 and 0.051032,respectively,implying that the digital optical switching regime can realize the low-loss low-power performance.Based on the feasible manufacturing conditions of the SOI platform,an appropriate device configuration is selected for fabrication and experimental tests,and the function of 1×3 or 1×2 digital optical switches is demonstrated.Finally,the theoretical and experimental results are summarized,and an improvement scheme of device performance is proposed.