Investigation of Temperature Sensitivity Under the Influence of Coupling Strength Between a Silica Core and a Satellite Waveguide in a Photonic Crystal Fiber with Selective Infiltration of Glycerin

In this report, we carry out simulation and experimental investigations of directional coupler structures with different separations between the glycerin selectively infiltrated channel and silica core of a large mode area Photonic Crystal Fiber (PCF). We assess their coupling characteristics and the corresponding temperature sensing capabilities. The temperature sensitivities of the glycerin selectively infiltrated channel adjacent to the silica core and two periods away from the silica core are −3.115 nm/°C and −2.332 nm/°C respectively. The glycerin selectively infiltrated channel three periods away from the silica core displays −107.8 pm/°C, an order of magnitude less temperature sensitive. The simulation results agree with the experimental results that there is a strong correlation between the coupling strength of the glycerin selectively infiltrated channel and the silica core, affecting its temperature response.