Tunable Single-Polarization Single-Mode Photonic Crystal Fiber Based on Liquid Infiltrating

We proposed and demonstrated a tunable single-polarization single-mode photonic crystal fiber (SPSM-PCF) based on selectively infiltrating liquid into air holes of high birefringence photonic crystal fiber (HB-PCF). A full-vector finite-element method (FEM) is used to analyze the SPSM operation range and its tunable characteristics. The starting wavelength of the SPSM operation range can be widely tuned from 2014 to 977 nm and the corresponding SPSM operation range can be tunable from 350 to 89 nm when the infiltrating index changes from 1.22 to 1.38. Experimentally, a tunable SPSM-PCF with a starting wavelength of SPSM operation range from 1591 to 1670 nm by increasing the temperature from 25
$^{\circ}$
C to 65
$^{\circ}$
C is realized. The tunable sensitivity is 1.975 nm/
$^{\circ}$
C and the extinction ratio of the two orthogonal polarized modes is 17 dB.