Abstract
We report a simple and compact optical fiber sensor based on surface relief gratings in conventional graded-index multimode optical fiber (GIMMF) for refractive index sensing. Bragg gratings on MMF are less explored compare to its single mode counterpart, even though the MMF platform possesses several advantages such as robustness, enhanced light-matter interaction and easy light coupling. In this work, surface relief gratings are directly written on one side of the cladding etched MMF core surface by using focused ion beam milling (FIB). A detailed theoretical analysis of the structure and sensing principle is analysed. The device performance as a refractive index sensor has been investigated experimentally by immersing the device in different concentration of NaCl solution. Experimental results show a sensitivity of 70 nm/RIU for a refractive index range of 1.333 to 1.345. The device is easy to fabricate with high repeatability and low cost, compact in design and competent to be used in harsh environmental conditions. The surface grating on etched MMF provides a better interaction between the sensing region and the environment which makes it a potential candidate for various chemical and biological sensing applications.
| Original language | English |
|---|---|
| Article number | 111836 |
| Journal | Sensors and Actuators, A: Physical |
| Volume | 303 |
| DOIs | |
| State | Published - 1 Mar 2020 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2020 Elsevier B.V.
Funding
Authors would like to acknowledge the financial support from DST Government of India projectDST/NM/NT/2018/9(G)and micro and nano fabrication facility (MRNF), IIT Kharagpur where the proposed devices are fabricated. Shailendra K. Varshney (SM’16) received the M.Sc. degree in physics fromAligarh Muslim University, Aligarh, India, in 1999, and the Ph.D. degree in applied physics (on photonic crystal fibers) from the University of Delhi, New Delhi, India, in 2005. In November 2008, he joined the Department of Electronics and Electrical Communication Engineering and the Department of Physics, Indian Institute of Technology (IIT) Kharagpur, Kharagpur, India, where he is currently an Associate Professor. He was a Monbukagakusho ResearchScholar (October 2002–March 2004), Postdoctoral Fellow on Center of Excellence project (August 2004–March 2007), and Postdoctoral Researcheron the Japan Society for Promotion of Science (JSPS) fellowship for foreign researchers between April 2007 and November 2008 with Hokkaido University, Sapporo, Japan. He is the recipient of several fellowships-UGC/CSIR JRFfellowship from the Government of India (2000–2002), the Monbukagakusho scholarship from the Government of Japan (October 2002–March 2004), theJSPS fellowship (April 2007-November 2008), and the Alexander von Humboldt fellowship from Germany (2009). He is the author and co-author of more than 65 research papers in peer-reviewed journals and more than 110 papers in conference proceedings. His research interests include PCF-based optical devices, on-chip photonic components and devices, application-specific specialty fibers, nonlinear photonics, quantum photonics, and optical wireless communication. He is a Senior Member of the Optical Society of America (OSA). Hewas the Faculty Advisor for the OSA's student chapter at IIT Kharagpur from 2013 to 2015. He is currently a traveling lecturer under the OSA program and the chair of the IEEE Kharagpur Section. Authors would like to acknowledge the financial support from D ST Government of India project DST/NM/NT/2018/9(G) and micro and nano fabrication facility ( MRNF ), IIT Kharagpur where the proposed devices are fabricated.
| Funders | Funder number |
|---|---|
| D ST Government of India | DST/NM/NT/2018/9 |
| DST Government of India | projectDST/NM/NT/2018/9 |
| Postdoctoral Researcheron the Japan Society for Promotion of Science | |
| Alexander von Humboldt-Stiftung | |
| Japan Society for the Promotion of Science | |
| Ministère des Ressources Naturelles et de la Faune |
Keywords
- Multimode optical fiber grating
- Optical fiber micro-machining
- Optical fiber sensor
- Refractive index sensor