Title :
Thermal Sensitivity of the Birefringence of Air-Core Fibers and Implications for the RFOG
Author :
Xiang Zhao ; Louveau, Joy ; Chamoun, Jacob ; Digonnet, Michel J. F.
Author_Institution :
Ginzton Lab., Stanford Univ., Stanford, CA, USA
Abstract :
We present an analytical model of the drift in the resonant fiber optic gyroscope (RFOG) caused by thermally induced changes in the fiber beat length LB(T) and find that the relevant metric for thermal-drift performance is not dLB/dT but rather (1/LB2)dLB/dT. This disfavors conventional solid-core PM fibers for which LB is very short and dLB/dT is large. Because the air core of hollow-core fibers does not support the strains associated with differential thermal expansion in conventional PM fibers, the birefringence of hollow-core fibers should be more thermally stable than conventional fibers with a correspondingly smaller (1/LB2)dLB/dT. To identify the relative merits of different types of fibers in the RFOG, we measure (1/LB2)dLB/dT for a variety of air-core and solid-core fibers by recording the shift in the resonance frequencies of an all-fiber ring resonator when its temperature is changed. We find that the PM air-core fiber offers a 270-fold improvement in (1/LB2)dLB/dT coefficient compared to a Panda fiber.
Keywords :
birefringence; fibre optic gyroscopes; optical fibre polarisation; optical fibre testing; optical resonators; temperature sensors; thermal expansion; thermal stability; PM air-core fiber; RFOG; all-fiber ring resonator; birefringence; differential thermal expansion; fiber beat length; hollow-core fibers; polarization-maintaining air-core fiber; resonance frequency; resonant fiber optic gyroscope; solid-core fibers; thermal sensitivity; thermal stability; thermal-drift performance; Optical fiber couplers; Optical fiber polarization; Optical fiber sensors; Optical ring resonators; Resonant frequency; Temperature measurement; Birefringence; inertial navigation; optical fiber applications; optical fiber devices; optical fiber sensors; optical fibers; optical resonators; thermal stability;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2014.2326163