Hollow Core Antiresonant Fiber Based Polarizer and Refractive Index Sensor

• Published in: Journal of lightwave technology 2024-01, Vol.42 (2), p.907-913
• Main Authors: Shaha, Kumary Sumi Rani, Khaleque, Abdul
• Format: Article
• Language: English
• Subjects: Antiresonant fiber; Birefringence; Cladding; Claddings; Coupling; Crosstalk; double ring; Electron tubes; hollow core fiber; nested tube; Optical fiber amplifiers; Optical fiber networks; Optical fiber polarization; Optical fiber sensors; Polarization; polarization extinction ratio; polarizer; Polarizers; refractive index sensor; Refractivity; Silicon; silicon coated layer; Tubes
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/JLT.2023.3320136

We propose a new single polarization guided antiresonant fiber design made of nested and double ring cladding tubes with a high index material layer coating that can function as a polarizer and sensor. The diverse cladding tube combinations along with a high index content layer enhance the fiber's ability to block one polarized ray through coupling effect and also provide minimal loss for other polarized ray by inhibited coupling mechanism. Besides, the development of two modes for the proposed structure are investigated where the cladding mode crosses with the core mode at desired wavelength, results light blocking for one polarization. Hence, the x -polarized ray's confinement loss founds 576 dB/m, where 0.0018 dB/m loss is experienced in y -polarization, allowing the maximal polarization extinction ratio of 320000 at 1.55 \mum along with >100 value for 40 nm bandwidth with a high birefringence of 0.55\times 10^{-4}. Moreover, the polarizing operation is successfully performed, where a crosstalk of larger than 20 dB for a compact length of 20 cm, is found from 1.538 \mum to 1.568 \mum of wavelength. Furthermore, the sensing performance is achieved as an example, such as the maximal wavelength sensitivity is found about 1293 nm/RIU for the fiber. Therefore, the simultaneous applications of the designed fiber make it an interesting device for optical systems.