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Optics Express

Optics Express

  • Editor: Michael Duncan
  • Vol. 11, Iss. 3 — Feb. 10, 2003
  • pp: 282–290

Small-area bends and beamsplitters for low-index-contrast waveguides

Lixia Li, Gregory P. Nordin, Jennifer M. English, and Jianhua Jiang  »View Author Affiliations

Optics Express, Vol. 11, Issue 3, pp. 282-290 (2003)

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We explore the use of air trenches to achieve compact high efficiency 90° waveguide bends and beamsplitters for waveguide material systems that have low refractive index and low refractive index contrast between the core and clad materials. For a single air interface, simulation results show that the optical efficiency of a waveguide bend can be increased from 78.4% to 99.2% by simply decreasing the bend angle from 90° to 60°. This can be explained by the angular spectrum of the waveguide mode optical field. For 90° bends we use a micro-genetic algorithm (µGA) with a 2-D finite difference time domain (FDTD) method to rigorously design high efficiency waveguide bends composed of multiple air trenches. Simulation results show an optical efficiency of 97.2% for an optimized bend composed of three air trenches. Similarly, a single air trench can be designed to function as a 90° beamsplitter with 98.5% total efficiency.

© 2003 Optical Society of America

OCIS Codes
(130.0130) Integrated optics : Integrated optics
(130.1750) Integrated optics : Components
(130.2790) Integrated optics : Guided waves
(130.3120) Integrated optics : Integrated optics devices
(250.5300) Optoelectronics : Photonic integrated circuits

ToC Category:
Research Papers

Original Manuscript: January 7, 2003
Revised Manuscript: February 3, 2003
Published: February 10, 2003

Lixia Li, Gregory Nordin, Jennifer English, and Jianhua Jiang, "Small-area bends and beamsplitters for lowindex-contrast waveguides," Opt. Express 11, 282-290 (2003)

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