Metal–Insulator–Silicon–Insulator–Metal Waveguide Splitters With Large-Arm Separation

Abstract

Symmetric 12 splitters of metal-insulator-siliconinsulator-metal (MISIM) waveguides, which are hybrid plasmonic waveguides with a 190-nm-wide silicon strip covered by 30-nm-thick SiO 2 and sandwiched by copper, are theoretically and experimentally investigated. The splitters consist of a Y-branch, two 90 submicrometer-radius bends (SRBs), and two straight MISIM waveguides connecting the Y-branch and the two SRBs. The Y-branch is an overlap of two oppositely-directed SRBs. All the SRBs of the splitter have the same radius of curvature. The splitter has a feature that the length of the in-between MISIM waveguides is adjusted to make its input waveguide split over a short distance into its widely-separated output waveguides. Simulation of the splitters indicates that the radius of curvature of the SRB needs to be  0.8 m to make small the excess losses of the splitters. When the radius of curvature is 0.8 m, the splitter which can connect its input waveguide just over 1.6 m to its output waveguides spaced 6.4 m apart has an excess loss of 1.4 dB. The splitters are realized by using standard CMOS technology. The measured excess losses of the fabricated splitters are larger than the calculated excess losses. However, the measured dependence of the excess loss on the radius of curvature is similar to the calculated one. Finally, the splitter feature is theoretically confirmed, and addition of a tapering region to the Y-branch is discussed to reduce the excess loss of the Y-branch.

Utilization of Field Enhancement in Plasmonic Waveguides for Subwavelength Light-Guiding, Polarization Handling, Heating, and Optical Sensing

“…The hybrid nanoplasmonic waveguides can also enable sub-μm 2 power splitters [ 79 , 80 ] as shown in Figure 4 a–c. From these figures, it can be seen that these sub-μm 2 power splitters, including 1 × 2 MMI (multimode interference) couplers, Y-branches and direction couplers (DCs) have ultrasmall footprints as well as high power transmissions of ~90% [ 79 ].…”

Programmable Multifunctional Plasmonic Waveguide System based on Coding Metamaterials and Inverse Design

“…8 The transmission of SPPs usually depends on special waveguide systems, for example metal-dielectric-metal (MDM) waveguide, 9 insulator-metal-insulator waveguide, 10 hybrid waveguide 11 and so on. Due to their compact footprint and easy integration, MDM waveguide systems have been widely applied in plasmonic filters, 12,13 splitters, 14,15 optical switches, 16 modulators, [16][17][18] absorbers, 19 sensors, 20 couplers, 21,22 logic gates 23 and so on. However, in order to realize different functions, researchers often spend much time on searching for and designing the nano-resonators with different shapes.…”

Tunable Terahertz Narrow-Band Plasmonic Filter Based on Optical Tamm Plasmon in Dual-Section InSb Slot Waveguide

“…Thus, many SP components have been demonstrated, such as reflectors, filters, splitters, photodetector, and optical amplifiers [2][3][4][5][6][7][8][9][10][11][12][13][14][15]. However, most of the efforts in SP components have been concentrated on near-infrared and optical frequencies.…”