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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 15, Iss. 22 — Oct. 29, 2007
  • pp: 14566–14572

Low-loss high-index-contrast planar waveguides with graded-index cladding layers

Juejun Hu, Ning-Ning Feng, Nathan Carlie, Laeticia Petit, Jianfei Wang, Anu Agarwal, Kathleen Richardson, and Lionel Kimerling  »View Author Affiliations

Optics Express, Vol. 15, Issue 22, pp. 14566-14572 (2007)

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We experimentally demonstrate, for the first time, propagation loss reduction via graded-index (GRIN) cladding layers in high-index-contrast (HIC) glass waveguides. We show that scattering loss arising from sidewall roughness can be significantly reduced without compromising the high-index-contrast condition, by inserting thin GRIN cladding layers with refractive indices intermediate between the core and topmost cover of a strip waveguide. Loss as low as 1.5 dB/cm is achieved in small core (1.6 μm × 0.35 μm), high-index-contrast (Δn = 1.37) arsenic-based sulfide strip waveguides. This GRIN cladding design is generally applicable to HIC waveguide systems such as Si/SiO2.

© 2007 Optical Society of America

OCIS Codes
(130.2790) Integrated optics : Guided waves
(130.3120) Integrated optics : Integrated optics devices
(160.2750) Materials : Glass and other amorphous materials
(230.7380) Optical devices : Waveguides, channeled
(240.5770) Optics at surfaces : Roughness
(310.1860) Thin films : Deposition and fabrication

ToC Category:
Integrated Optics

Original Manuscript: August 27, 2007
Revised Manuscript: October 16, 2007
Manuscript Accepted: October 18, 2007
Published: October 19, 2007

Juejun Hu, Ning-Ning Feng, Nathan Carlie, Laeticia Petit, Jianfei Wang, Anu Agarwal, Kathleen Richardson, and Lionel Kimerling, "Low-loss high-index-contrast planar waveguides with graded-index cladding layers," Opt. Express 15, 14566-14572 (2007)

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