Optimization of Thermo-Optic Parameters for Temperature-Insensitive LPWG Refractometers

ETRI Journal

关键词: refractive index sensors;    photonic integrated circuit;    planar waveguide;    long-period grating (LPG);    Bragg grating;   

Others  :  1185326
DOI  :  10.4218/etrij.06.0106.0180

【 摘 要 】

In this paper, we report numerically calculated results of testing a temperature-insensitive refractive sensor based on a planar-type long-period waveguide grating (LPWG). The LPWG consists of properly chosen polymer materials with an optimized thermo-optic coefficient for the core layer in a four-layer waveguide structure. The resonant wavelength shift below the spectral resolution of the conventional optical spectrum analyzer is obtained accurately over a temperature change of ±7.5C even without any temperature control. The refractive index sensitivity of the proposed grating scheme is about 0.004 per resonant wavelength shift of 0.1 nm for an optimized thermo-optic coefficient.

   

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