Abstract-A modified hexagonal photonic crystal fiber for terahertz applications

https://www.sciencedirect.com/science/article/pii/S0925346718301873


We present a Zeonex based highly birefringent and dispersion flattened porous core photonic crystal fiber (PC-PCF) for polarization preserving applications in the terahertz region. In order to facilitate birefringence, an array of elliptical shaped air holes surrounded by porous cladding is introduced. The porous cladding comprises circular air-holes in a modified hexagonal arrangement. The transmission characteristics of the proposed PCF are investigated using a full-vector finite element method with perfectly matched layer (PML) absorbing boundary conditions. Simulation results show a high birefringence of 0.086 and an ultra-flattened dispersion variation of 
$\pm 0.03$ ps/THz/cm at optimal design parameters. Besides, a number of other important wave-guiding properties including frequency dependence of the effective material loss (EML), confinement loss, and effective area are also investigated to assess the fiber’s effectiveness as a terahertz waveguide.

Abstract-Zeonex-based asymmetrical terahertz photonic crystal fiber for multichannel communication and polarization maintaining applications

Md. Saiful Islam, Jakeya Sultana, Alex Dinovitser, Mohammad Faisal, Mohammad Rakibul Islam, Brian W.-H. Ng, and Derek Abbott

https://www.osapublishing.org/ao/abstract.cfm?uri=ao-57-4-666&origin=search

We report on the design, in-depth analysis, and characterization of a novel elliptical array shaped core rectangular shaped cladded photonic crystal fiber (PCF) for multichannel communication and polarization maintaining applications of terahertz waves. The asymmetrical structure of air holes in both core and cladding results in increased birefringence, while a compact geometry and different cladding air hole size makes the dispersion characteristic flat. The modal characteristics of the PCF are calculated using a finite element method. The simulated results show a near-zero dispersion flattened property of ±0.02  ps/THz/cm$\pm 0.02\mathrm{ps}/\mathrm{THz}/\mathrm{cm}$, high birefringence of 0.063, low effective material loss of 0.06  cm−1$0.06{\mathrm{cm}}^{-1}$, and negligible confinement loss of 5.45×10−13  cm−1$5.45\times {10}^{-13}{\mathrm{cm}}^{-1}$ in the terahertz frequency range. Additionally, the core power fraction, effective area, physical attributes, and potential fabrication possibilities of the fiber are discussed.

© 2018 Optical Society of America

Abstract-Highly birefringent elliptical core photonic crystal fiber for terahertz application

Jakeya Sultana, Md. Saifu lIslam, Mohammad Faisal, Mohammad Rakibul Islam, Brian W.-H.Ng, Heike Ebendorff-Heidepriem, Derek Abbott


http://www.sciencedirect.com/science/article/pii/S0030401817307812

We present a novel strategy for designing a highly birefringent photonic crystal fiber (PCF) with near zero flattened dispersion properties by applying elliptical air holes in the core area. The elliptical structure of the air holes in the porous-core region introduces asymmetry between  and  polarization modes, which consequently offers ultra-high birefringence. Also the compact geometry of the conventional hexagonal structure in the cladding confines most of the useful power. The optical properties including birefringence, dispersion, confinement loss, effective material loss (EML) and single modeness of the fiber are investigated using a full-vector finite element method. Simulation results show an ultra-high birefringence of  ultra-flattened near zero dispersion of  ps/THz/cm in a broad frequency range. The practical implementation of the proposed fiber is feasible using existing fabrication technology and is applicable to the areas of terahertz sensing and polarization maintaining systems.

Abstract-Extremely low loss porous-core photonic crystal fiber with ultra-flat dispersion in terahertz regime

Md. Shariful Islam, Mohammad Faisal, and S. M. Abdur Razzak

https://www.osapublishing.org/josab/abstract.cfm?uri=josab-34-8-1747&origin=search


An extremely low loss porous-core fiber with nearly zero dispersion flattened over a wide band of frequency in the terahertz (THz) regime is presented in this paper. A novel structure of hexagonal air holes in both the core and the cladding is introduced to provide an overwhelming reduction in bulk material absorption loss and confinement loss. Numerical analysis shows that an effective material loss as low as 

0.0206  cm−1$0.0206{\mathrm{cm}}^{-1}$ and a very flat dispersion of ±0.16  ps/THz/cm$\pm 0.16\mathrm{ps}/\mathrm{THz}/\mathrm{cm}$can be obtained from the proposed fiber in the frequency range of 0.98–1.64 THz. Within the whole frequency band, the fiber operates in a single-mode region and shows a variation in total loss of only ±0.01  cm−1$\pm 0.01{\mathrm{cm}}^{-1}$.

© 2017 Optical Society of America

Abstract-Highly birefringent elliptical core photonic crystal fiber for terahertz application

Jakeya Sultana, Md. SaifulIslam, Mohammad Faisal, Mohammad RakibulIslam, Brian W.-H.Ng, Heike Ebendorff-Heidepriemd, DerekAbbot

http://www.sciencedirect.com/science/article/pii/S0030401817307812

We present a novel strategy for designing a highly birefringent photonic crystal fiber (PCF) with near zero flattened dispersion properties by applying elliptical air holes in the core area. The elliptical structure of the air holes in the porous-core region introduces asymmetry between $x$ and $y$ polarization modes, which consequently offers ultra-high birefringence. Also the compact geometry of the conventional hexagonal structure in the cladding confines most of the useful power. The optical properties including birefringence, dispersion, confinement loss, effective material loss (EML) and single modeness of the fiber are investigated using a full-vector finite element method. Simulation results show an ultra-high birefringence of $0.086$ ultra-flattened near zero dispersion of $0.53\pm 0.07$ ps/THz/cm in a broad frequency range. The practical implementation of the proposed fiber is feasible using existing fabrication technology and is applicable to the areas of terahertz sensing and polarization maintaining systems.