Giant refractometric sensitivity by combining extreme optical Vernier effect and modal interference

• Type: Article in International Scientific Journal
• Date: 2020

Authors

Gomes, AD (Author) Other; Kobelke, J (Author) Other; Bierlich, J (Author) Other; Dellith, J (Author) Other; Rothhardt, M (Author) Other; Bartelt, H (Author) Other; Frazao, O (Author) FCUP

Journal

Title: Scientific Reports

Vol. 10

ISSN: 2045-2322

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 0 Citations

Scopus - 0 Citations

Other information

Authenticus ID: P-00T-0BJ

DOI: 10.1038/s41598-020-76324-7

Abstract (EN): The optical Vernier effect consists of overlapping responses of a sensing and a reference interferometer with slightly shifted interferometric frequencies. The beating modulation thus generated presents high magnified sensitivity and resolution compared to the sensing interferometer, if the two interferometers are slightly out of tune with each other. However, the outcome of such a condition is a large beating modulation, immeasurable by conventional detection systems due to practical limitations of the usable spectral range. We propose a method to surpass this limitation by using a few-mode sensing interferometer instead of a single-mode one. The overlap response of the different modes produces a measurable envelope, whilst preserving an extremely high magnification factor, an order of magnification higher than current state-of-the-art performances. Furthermore, we demonstrate the application of that method in the development of a giant sensitivity fibre refractometer with a sensitivity of around 500 mu m/RIU (refractive index unit) and with a magnification factor over 850.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 14