Highly birefringent microstructured polymer fibers optimized for a preform drilling fabrication method

Abstract

We propose two designs of birefringent microstructured fibers assuring high geometrical birefringence in the visible range and low confinement losses. An increased birefringence level in the visible range is achieved by breaking the hexagonal symmetry of the structure and shifting selected holes with respect to the nodes of the hexagonal lattice. Such geometry of the microstructured cladding is feasible for polymer fibers fabricated using a preform drilling method. In the first optimized design, two large air-holes adjacent to the core are shifted towards each other to increase modal birefringence. In the second design, high birefringence is achieved by approaching two regions with large holes separated by a row of smaller holes. The simulation results show that in the first fiber with a pitch distance of 3.0 μm, it is possible to obtain a phase birefringence of the fundamental mode greater than 1 × 10−4, while the confinement losses do not exceed 0.06 dB m−1 in the visible range. In the second fiber with the same pitch distance, the confinement losses are smaller than 0.3 dB m−1 in the spectral range of 500–1100 nm, while the phase modal birefringence exceeds 1 × 10−4 in the visible range and reaches 4.0 × 10−4 at 633 nm. We also present the fiber fabricated according to the second design and compare the calculated and the measured spectral dependence of birefringence.

Suspended-Core Microstructured Polymer Optical Fibers and Potential Applications in Sensing

“…Drilling is a straightforward approach for the fabrication of MPOF preforms. The structure preform is created by drilling the pattern of holes into a solid polymer rod using a drill or a laser (Figure 3) which is connected with an XY translation stage to create the required pattern [30,31,32,33]. Using computer numerical control (CNC) machining it is possible to execute a sequence of automatized instructions over a monolithic polymer cylinder to fabricate complex structured preforms with high resolution.…”

Molecular alignment relaxation in polymer optical fibers for sensing applications

“…Here we note that we use the same PMMA rod type only with larger diameter for fabrication of our standard mPOFs by the preform drilling method [15]. The level of induced molecular alignment is a complex function of various drawing conditions, where fiber drawing stress is the key pointer for determining the alignment degree.…”

Fabrication of Low Loss and Near Zero Dispersion Suspended Core Polypropylene Fibers for Terahertz Communications Using Infinity 3D Printing Technique

“…Otherwise, the waveguide that cannot be manufactured or is extremely difficult to be manufactured has to struggle in the theoretical stage even if its performance is excellent. In the last few years, several conventional methods are widely used in the fabrication of the MPWG, such as drill and draw technique [39][40][41] which can easily adjust the structural parameters of preforms with high accuracy by using computer numerical control (CNC) machining; stack and draw technique [42] which has advantages in fabricating waveguides with high porosity by stacking many tubes with large pores; casting and draw technique [43]which provides superiority over stacking since it is easier to adjust the porosity, arrangement of pores, and doesn't produce unnecessary gaps as stacking tubes. However, these conventional methods divide the manufacturing of waveguides into two steps, manufacturing preforms and drawing into waveguides, which inevitably increase the workload.…”