Abstract:
Photonic crystal fiber (PCF) is one kind of optical fiber having a number of air holes arranged
in a crystal running longitudinally in its structure. It plays vital role in fiber optic
communication systems where extensive research has been done for the past few years. THz
electromagnetic transmission (0.1-10 THz) has been an area of increasing interest and
extensive research over the past few years. PCFs have shown promising applications in THz
transmission domain due to their design flexibility and simultaneous air-solid guiding
mechanism.
In this thesis, different properties of PCF like dispersion, birefringence, confinement loss,
power fraction etc. are investigated numerically by a full vectorial FEM. Two porous core
octagonal photonic crystal fiber (PCF) for terahertz (THz) wave propagation are proposed in
our thesis. One of the design is highly birefringent photonic crystal fiber (PCF) with all
circular holes for transmission in the terahertz (THz) regime. It shows a very high
birefringence about 0.045 at 1 THz and flattened dispersion of 2.2±0.09 ps/THz/cm within
0.7 THz to 0.95 THz. And the other design exhibits low loss properties. A very low material
absorption loss (0.076𝑐𝑚−1) and low confinement loss (0.0006𝑐𝑚−1) are obtained from the
proposed design. This two designs are expected to be useful for efficient transmission of
broadband terahertz radiation.
Description:
First of all, we would like to thank Allah for giving us the ability to complete this thesis work.
We would like to express our utmost gratitude towards our honorable supervisor, Dr.
Mohammad Faisal, without whose encouragement and guidance, this thesis would have
never been completed. We are very grateful for his continuous instructions and
encouragement, valuable discussions and careful review during the entire duration of the
research. His thoughtful analyses and firm supervision have provided us with the right
direction towards our goal. We have learned many valuable concepts of Optical fiber
Communication from him throughout our study, which we tried to utilize and develop our
analyzing abilities. His constant encouragement gave us the confidence to carry out our work.
We would also like to thank all our teachers. They gave the knowledge and directions needed
throughout my life. We express our gratitude towards our teachers from Military Institute of
Science and Technology (MIST). I want to thank my friends for providing me support and
encouragement. Their suggestions helped me in countless ways.
Last but not the least, we would like to thank our parents. Their unconditional support made
it possible to finish this thesis.
