Spectral Tuning of Long Period Fiber Gratings Fabricated by Femtosecond Laser Micromachining through Thermal Annealing

• Type: Article in International Scientific Journal
• Date: 2019

Authors

Viveiros, D (Author) FCUP; de Almeida, JMMM (Author) FCUP; Coelho, L (Author) FCUP; Vasconcelos, H (Author) Other; Amorim, VA (Author) Other; Maia, JM (Author) Other; Jorge, PAS (Author) FCUP

Journal

Title: Proceedings

Vol. 15 No. 1

Final page: 4

ISSN: 2504-3900

Publisher: MDPI

Other information

Authenticus ID: P-00Q-SFS

DOI: 10.3390/proceedings2019015004

Abstract (EN): <jats:p>A femtosecond laser direct writing system was developed to explore the fabrication of long-period fiber gratings (LPFGs) in SMF28 fibers. The LPFGs, showing the mode LP1,6 at 1500 nm, were exposed to high-temperature annealing up to 950 °C. Modifications in the refractive index (RI) modulation are observed through a blue-shift in the LPFG attenuation bands and above 850 °C, the mode LP1,7 appear at 1600 nm. The wavelength sensitivity to external RI from 1.300 to 1.452 was estimated for both modes before and after annealing. Greater sensitivity was found for the higher order mode in the entire range reaching 2400 nm/RIU around 1.440.</jats:p>

Language: English

Type (Professor's evaluation): Scientific