The design of a novel photonic crystal waveguide power splitter is presented. The proposed power splitter has three output ports, the coupling among three parallel photonic crystal waveguides can be considered as a multimode interference (MMI), and the positions of output waveguides are determined by those of twofold images which are formed by the self-imaging effect of multimode interference. The transmission characteristics of the splitter are investigated by using the finite-difference time domain (FDTD) and the plane wave expansion method. The output optical power in each port can be controlled by adjusting the radius of the dielectric rods in the coupling region, and the coupling effect among output ports is decreased by using the T-shaped output port. The results indicate that 1 1 1 2 and 1 3 type power splitters can be realized when the normalized radius of dielectric rods in the coupling region is 0.130, 0.180, 0.152 or 0.221, respectively.Photonic crystals (PCs) [1,2 ] have defect modes [3] in the band gaps by introducing defects in perfect photonic crystals, and optical waveguides can be constructed by introducing linear defects which confirm that there is no radiation loss through sharp bends in photonic crystal waveguides [4] . The directional coupling can happen between two or more photonic crystal waveguides, based on which couplers such as splitters [5] , optical switchng [6] and wavelength division multiplexer/ demultiplexer (WDMD) [7] can be formed. Multimode interference (MMI) [8] devices based on self-imaging effect [9] are important components in photonic integrated devices. Due to their simple structure, low loss, and large optical bandwidth, we can design all optical switching [10] , TE/TM polarization splitter [11] and filter [12] . MMI devices have been widely used in the field of optical communications.The design of a novel photonic crystal power splitter is reported in this paper. The coupling among three parallel photonic crystal waveguides can be considered as a multimode interference, and the positions of output waveguides are determined by those of twofold images formed by the self-imaging effect of multimode interference. The 1 1, 1 2 and 1 3 type splitters can be realized based on the same structure.The structure is the dielectric rod photonic crystal with two-dimensional (2D) square lattice surrounded by the air (n l = 1.00), and the dielectric constant is r = 11.56. The ratio of rod radius to lattice constant is set to be 0.18. The coupling among three parallel photonic crystal waveguides can be considered as a multimode interference. Selecting the supercell shown in Fig.1 and using the plane wave expansion method [13] , the dispersion curve of the photonic crystal multimode waveguide can be solved, which is shown in Fig.2. Influenced by the self-imaging effect of multimode interference, the position of 1-fold image is determined byThe position of 2-fold image is determined by L = 2 k/( 0 2 ) k=1, 2, 3,(1) L = (2k 1) ( 0 2 ) k=1,2,3,where 0 = 0.3150 2 /a and 2 = 0.2746 2 /a at a/...
In the design process of a novel photonic crystal 1 4 power splitter, the coupling of three parallel photonic crystal waveguides can be considered as a multimode interference system in the two-dimensional square photonic crystal, the positions of output waveguides are decided by the positions of periodic twofold image which are formed by the self-imaging effect of multimode interference.The identical output optical power in each output port of the device can be realized by inserting dielectric rod E and F in the junction between the multimode waveguides and lateral single-mode output waveguides.The transmission characteristics of the splitter are investigated by using the finite-difference time-domain method.The results show that the transmittance of this splitter can be as high as 95.4% for =1.55 m when the radius of the inserted dielectric rods of E and F is 0.34r.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.