High-resolution measurement of birefringence profiles in stress-induced polarization-maintaining fibers

Abstract

A novel technique to measure the local refractive-index anisotropy in stress-induced polarization-maintaining fibers is presented. The application of this technique to two different types of fibers reveals birefringence profiles as well as differential stress profiles. The measurement results are verified by independently measured modal birefringence and calculated stress profiles.

Characterization of Bragg gratings in normal and reduced diameter HiBi fibers

“…The faster rate agrees with the optical observation of the etched samples, where the attack along the minor axis of the ellipse can lead to the core destruction and separation of the remaining halves. The above behavior agrees with the intrinsic birefringence measurements obtained from FBG in HiBi fibers [7] and from previous measurements concerning such fibers [ 6 ] , that show IEC HiBi fibers as having the highest stress-induced birefringence, that is, the difference between stress components along principal axes of the refractive index profile is also highest. Chemical etching is too influenced by the stress distribution in the glass.…”

“…Previous studies with IEC libers have revealed that a strong differential stress (0, -0,) exists in the interface between the external cladding and the elliptical stressapplying region [6], but this behavior has been observed only along the major axis of the ellipse. After a peak at the interface, the differential stress penetrates with high values (greater than the values inside the ellipse) into the cladding.…”

“…After a peak at the interface, the differential stress penetrates with high values (greater than the values inside the ellipse) into the cladding. Along the minor axis the differential stress is greater inside the ellipse (compared to the value along major axis) but only drops monotonically to zero across the interface to the cladding [6]. Figure 3 shows the changes in the transversal section of the optical fiber after two exposure times to the 20 % concentration HF etching.…”

Asymmetric core photonic‐crystal fibers with high birefringence

“…To conventional polarization-maintaining fiber, the stress-induced anisotropy is more efficient in generating birefringence than the geometrical shape of the core, because of the small core-cladding index difference [6]. For PCF with high birefringence, as demonstrated in [1][2][3][4][5], only geometrical anisotropy was utilized.…”

“…Dielectric parameters of human blood at microwave frequencies using coaxial line and the waveguide method were reported by Cook [4]. Also, human tissue samples were studied at microwave frequencies by Cook [5] and Land et al [6]. Sample cell-terminated transmission-line methods have obtained good response at lower microwave frequency, but the accuracy is very much comprised at higher microwave frequencies [5,7,8].…”