Design of Compact TE-Polarized Mode-Order Converter in Silicon Waveguide With High Refractive Index Material

• Published in: IEEE photonics journal Vol. 10; no. 6; pp. 1 - 7
• Main Authors: Zhu, Danfeng, Ye, Han, Yu, Zhongyuan, Li, Jing, Yu, Fengyi, Liu, Yumin
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.12.2018; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Computer simulation; Conversion; Converters; Division; Electric fields; Fabrication; Finite difference method; Integrated optics devices; Mode conversion; Multiplexing; Optical waveguides; Photonics; Refractive index; Refractivity; Robustness (mathematics); Silicon; Silicon waveguide; Slabs; Time domain analysis; Transmittance; Transverse magnetic modes
• ISSN: 1943-0655; 1943-0655; 1943-0647
• DOI: 10.1109/JPHOT.2018.2883209

We propose and numerically demonstrate a design of bidirectional transverse electric (TE) polarized mode-order converter based on silicon-on-insulator platform. This converter is realized by introducing high refractive index material inlaid in a silicon slab waveguide. Simulated by three-dimensional finite-difference method time-domain, the forward (TE0 to TE1-like conversion) transmittance reaches approximately 88.2%, while the backward value (TE1 to TE0-like conversion) is about 89.4% at the wavelength of 1550 nm. The footprint of this converter is as small as 0.95 × 1.5 μm 2 . Fabrication tolerance analysis demonstrates satisfactory robustness. Moreover, we present a polarization-independent converter with slightly modified geometry. The transmittance keeps above 87.2% within the wavelength range from 1500 nm to 1600 nm for both TE and transverse magnetic modes. These devices are expected to contribute to the on-chip mode division multiplexing.