Ultra-broadband mid-infrared Ge-on-Si waveguide polarization rotator

Gallacher, K. , Millar, R. W. , Griskeviciute, U., Sinclair, M. , Sorel, M. , Baldassarre, L., Ortolani, M., Soref, R. and Paul, D. J. (2020) Ultra-broadband mid-infrared Ge-on-Si waveguide polarization rotator. APL Photonics, 5(2), 026102. (doi: 10.1063/1.5134973)

Abstract

The design, modeling, micro-fabrication, and characterization of an ultra-broadband Ge-on-Si waveguide polarization rotator are presented. The polarization rotator is based on the mode evolution approach where adiabatic symmetric and anti-symmetric tapers are utilized to convert from the fundamental transverse magnetic to electric mode. The device is shown to be extremely fabrication tolerant and simple to fabricate. The fabricated devices demonstrate a polarization extinction ratio of ≥15 dB over a 2 μm bandwidth (9–11 μm wavelength) with an average insertion loss of <1 dB, which is an order of magnitude improvement compared to previously demonstrated devices. This device will provide polarization flexibility when integrating quantum cascade lasers on-chip for mid-infrared waveguide molecular spectroscopy.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Millar, Dr Ross and Sinclair, Mr Martin and Sorel, Professor Marc and Hawley, Mrs Ugne and Paul, Professor Douglas and Gallacher, Dr Kevin
• Authors: Gallacher, K., Millar, R. W., Griskeviciute, U., Sinclair, M., Sorel, M., Baldassarre, L., Ortolani, M., Soref, R., and Paul, D. J.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: APL Photonics
• Publisher: AIP Publishing
• ISSN: 2378-0967
• ISSN (Online): 2378-0967
• Published Online: 18 February 2020
• Copyright Holders: Copyright © 2020 The Authors
• First Published: First published in APL Photonics 5(2):026102
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
171911		Engineering Quantum Technology Systems on a Silicon Platform	Douglas Paul	Engineering and Physical Sciences Research Council (EPSRC)	EP/N003225/1	ENG - Electronics & Nanoscale Engineering
305161		Germanium Tin Quantum Detectors	Ross Millar	Royal Academy of Engineering (RAE)	RF/201819/18/187	ENG - Electronics & Nanoscale Engineering