High-confinement alumina waveguides with sub-dB/cm propagation losses at 450 nm

McKay, E., Pruiti, N. G. , May, S. and Sorel, M. (2023) High-confinement alumina waveguides with sub-dB/cm propagation losses at 450 nm. Scientific Reports, 13, 19917. (doi: 10.1038/s41598-023-46877-4) (PMID:37963923)

Abstract

Amorphous alumina is highly transparent across the visible spectrum, making it a promising candidate for low-loss waveguiding at short wavelengths. However, previous alumina waveguide demonstrations in the visible region have focused on low- to moderate-confinement waveguides, where the diffuse mode reduces the design flexibility and integration density of photonic integrated circuits. Here, we have developed a high-quality etch mask and a highly selective BCl3 plasma etch, allowing etching of amorphous alumina waveguides up to 800 nm thick. Using this process, we have fabricated waveguides using an alumina film grown by atomic layer deposition (ALD) which are the lowest-loss high-confinement waveguides for blue light to date: we achieve single-mode propagation losses of 0.8 dB/cm at a propagation wavelength of 450 nm.

• Item Type: Articles
• Additional Information: This work is supported by the Defence Science and Technology Laboratory (306517).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Pruiti, Mr Natale and May, Mr Stuart and McKay, Ms Elissa and Sorel, Professor Marc
• Authors: McKay, E., Pruiti, N. G., May, S., and Sorel, M.
• College/School: College of Science and Engineering > School of Engineering; College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: Scientific Reports
• Publisher: Nature Research
• ISSN: 2045-2322
• ISSN (Online): 2045-2322
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Scientific Reports 13:19917
• Publisher Policy: Reproduced under a Creative Commons licence