Low Loss Germanium-on-Silicon Waveguides for Integrated Mid-Infrared Photonics

Millar, R. W. , Gallacher, K. , Griskeviciute, U., Baldassarre, L., Sorel, M. , Ortolani, M. and Paul, D. J. (2019) Low Loss Germanium-on-Silicon Waveguides for Integrated Mid-Infrared Photonics. In: SPIE OPTO 2019, San Francisco, CA, USA, 02-07 Feb 2019, 109230S. (doi: 10.1117/12.2510009)

Abstract

Low loss Ge-on-Si waveguides are demonstrated in the 8 – 14 μm atmospheric transmission window, a technology that will enable detection and sensing of unique molecular vibrations. Such a low cost platform would have applications in key markets such as pollution monitoring, explosives detection and point of care diagnostics. Rib-waveguides are fabricated using electron beam lithography and dry etching. The waveguides propagation losses are characterized using the Fabry-Perot technique, and are found to be below 5 dB/cm across the measurement range of 7.5 to 11 μm wavelength, reaching as low as ~ 1 dB/cm. The contribution to the losses are analyzed using the experimentally measured Si substrate losses, and the calculated scattering losses from an analytical model. The results verify the feasibility of the Ge-on-Si platform for integrated mid-infrared photonics and sensing.

• Item Type: Conference Proceedings
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Millar, Dr Ross and Sorel, Professor Marc and Hawley, Mrs Ugne and Paul, Professor Douglas and Gallacher, Dr Kevin
• Authors: Millar, R. W., Gallacher, K., Griskeviciute, U., Baldassarre, L., Sorel, M., Ortolani, M., and Paul, D. J.
• College/School: College of Science and Engineering > School of Engineering; College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• ISSN: 0277-786X
• Copyright Holders: Copyright © 2019 SPIE
• First Published: First published in Proceedings of SPIE 10923: 109230S
• Publisher Policy: Reproduced in accordance with the publisher copyright policy