Femtosecond laser micromachining of suspended silica-core liquid-cladding waveguides inside a microfluidic channel

• Type: Article in International Scientific Journal
• Date: 2022

Authors

Maia, JM (Author) Other; Viveiros, D (Author) Other; Amorim, VA (Author) Other; Marques, PVS (Author) FCUP

Journal

Title: Optics and Lasers in Engineering

Vol. 154

ISSN: 0143-8166

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 2 Citations

Scopus - 2 Citations

Other information

Authenticus ID: P-00W-7PF

DOI: 10.1016/j.optlaseng.2022.107016

Abstract (EN): This work addresses the fabrication of straight silica-core liquid-cladding suspended waveguides inside a microfluidic channel through fs-laser micromachining. These structures enable the reconfiguration of the waveguide's mode profile and enhance the evanescent interaction between light and analyte. Further, their geometry resembles a tapered optical fiber with the added advantage of being monolithically integrated within a microfluidic platform. The fabrication process includes an additional post-processing thermal treatment responsible for smoothening the waveguide surface and reshaping it into a circular cross-section. Suspended waveguides with a minimum core diameter of 3.8 mu m were fabricated. Their insertion losses can be tuned and are mainly affected by mode mismatch between the coupling and suspended waveguides. The transmission spectrum was studied and it was numerically confirmed that it consists of interference between the guided LP01 mode and uncoupled light and of modal interference between the LP01 and LP02 modes.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8