Thermal tunability of photonic bandgaps in liquid crystal filled polymer photonic crystal fiber

• A highly tunable liquid crystal filled polymer photonic crystal fiber is designed.
• Structural parameter dependence/thermal tunability of the PBGs are investigated.
• High thermal tuning sensitivity of the PBGs is achieved around room temperature.

A highly tunable bandgap-guiding polymer photonic crystal fiber is designed by infiltrating the cladding air holes with liquid crystal 5CB. Structural parameter dependence and thermal tunability of the photonic bandgaps, mode properties and confinement losses of the designed fiber are investigated. Bandgaps red shift as the temperature goes up. Average thermal tuning sensitivity of 30.9 nm/°C and 20.6 nm/°C is achieved around room temperature for the first and second photonic bandgap, respectively. Our results provide theoretical references for applications of polymer photonic crystal fiber in sensing and tunable fiber-optic devices.