Abstract
In this Letter we report on fabricating and analyzing a temperature insensitive refractometer based on two concatenated dual-resonance long-period gratings (LPGs) with an appropriate inter-grating space (IGS) in between. The IGS provides a temperature-dependent extra phase difference between the core and cladding modes, making the refractometer similar to a Mach–Zehnder interferometer with its arms phase shifted. We demonstrate that an appropriate IGS can produce temperature-insensitive resonance wavelengths. The interferometer is highly stable over a wide range of temperature (20°C–100°C). The measured refractive index sensitivity for aqueous solutions (1.333–1.343) is , which is the highest reported so far for biological samples. The interferometer can be used for various other temperature-immune sensing applications also.
© 2013 Optical Society of America
Full Article | PDF ArticleMore Like This
Ruchi Garg and K. Thyagarajan
Appl. Opt. 52(10) 2086-2092 (2013)
Dora Juan Juan Hu, Jun Long Lim, Meng Jiang, Yixin Wang, Feng Luan, Perry Ping Shum, Huifeng Wei, and Weijun Tong
Opt. Lett. 37(12) 2283-2285 (2012)
Dae Woong Kim, Fabin Shen, Xiaopei Chen, and Anbo Wang
Opt. Lett. 30(22) 3000-3002 (2005)