We characterized the temperature sensitivity of birefringence of typical solid core polarization maintaining photonic
crystal fiber (PM-PCF). Mainly the temperature dependence of birefringence is determined by two factors which are
thermo-optic effects and thermal expansion. Numerical simulation with ANSYS and RSOFT show that the birefringence
temperature susceptibility can be described as a polynomial function of Λ (distance between small holes) and zero
temperature coefficient may be obtained at optimum Λ. A high precision birefringence measure setup was built and the
birefringence of five PM-PCFs samples with different Λ were measured under different temperature. The experimental
result agreed well with the simulation.
An embedded pressure sensor was made by sandwiching a polarization maintaining photonic crystal fiber (PM-PCF)
between two polymer foils. The excess birefringence induced by transverse pressure applied along the slow-axis of a
PM-PCF was numerically simulated with a finite element method. Experiment was carried out with a Sagnac
interferometer with the embedded PM-PCF as part of the Sagnac loop. The output interference fringes were found shift
linearly with applied transverse pressure with a wavelength to pressure sensitivity of 1.764 nm/MPa, The measurement
precision of 0.2%, and a dynamic range of 2.5 MPa were achieved.
Polarization maintaining (PM) photonic crystal fiber (PCF) and Er-doped PCF technologies are investigated for
interferometer fiber optic gyroscope (IFOG) applications. A PM-PCF optimized to achieve low-loss and high
polarization extinction splice-joints with conventional PM fiber pigtails of a multifunction integrated optical circuit
(MIOC) was drawn and tested under different temperature conditions. The loss and polarization crosstalk
properties of a fiber coil made from the PM PCF were measured and compared with conventional PM fiber. An
erbium-doped PCF was designed and fabricated, with which a superfluorescent fiber source (SFS) was made and tested.
The results show that an IFOG with the PM-PCF coil and the Er-doped PCF source could achieve better temperature
performance. An experimental PCF-based prototype IFOG was built and tested , and preliminary results was obtained.