Graphene-oxide coated LPGs for humidity sensing applications

Namita Sahoo; Zhongyuan Sun; Kaiming Zhou; Xianfeng Chen; Yidong Tan; Lin Zhang

doi:10.1117/12.2555365

1 April 2020 Graphene-oxide coated LPGs for humidity sensing applications

Namita Sahoo, Zhongyuan Sun, Kaiming Zhou, Xianfeng Chen, Yidong Tan, Lin Zhang

Proceedings Volume 11355, Micro-Structured and Specialty Optical Fibres VI; 1135505 (2020) https://doi.org/10.1117/12.2555365
Event: SPIE Photonics Europe, 2020, Online Only

Abstract

In this paper, we report a highly effective relative humidity (RH) sensor implemented on graphene oxide (GO) coated long period grating (LPG). The GO nanocolloides bonded onto a cylindrical fibre cladding enables the LPG with strong evanescent waves to absorb more water molecules increasing its RH sensitivity. In an LPG, the phase matching condition occurs when a forward propagating core mode is coupled with the co-propagating lower order cladding modes generating evanescent waves to interact with the surrounding medium. This unique effect of LPGs can be more enhanced with multilayer GO deposition. There is an expansion of GO film with the absorption of more water molecules as RH increases. The absorption of water molecules on GO coating increases the conducting carrier (holes) density on it, thus decreasing the refractive index of GO film. The combined effect of increasing evanescent waves and modulated refractive index makes the GO coated LPGs as effective RH sensors. Our recently achieved results have shown the RH sensitivity of the GO coated LPG is about 0.01 dB/%RH. We have also investigated the effect on GO layer thickness, showing thicker layer increases the RH response of the LPG cladding mode resonances in lower wavelength region.

Conference Presentation

Citation Download Citation

Namita Sahoo, Zhongyuan Sun, Kaiming Zhou, Xianfeng Chen, Yidong Tan, and Lin Zhang "Graphene-oxide coated LPGs for humidity sensing applications", Proc. SPIE 11355, Micro-Structured and Specialty Optical Fibres VI, 1135505 (1 April 2020); https://doi.org/10.1117/12.2555365

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available