Abstract:
This thesis characterizes a hollow core dielectric waveguide with metal wires inclusion fabricated with a 3D printer. The numerical and experimental investigation are conducted to obtain some physical parameters of the waveguide. The waveguide is constructed as a hollow dielectric tube with 12 small holes surrounded the cladding. Later, several number of copper wires are attached on the selected holes to establish a boundary condition in the core-cladding interface. Therefore, the mode can be confined in the air core region. The 3D printing technique is chosen as a method to manufacture our waveguides, since it has a good accuracy and it is able to fabricate a complex waveguide structure. The fundamental mode HE11 can be guided in the waveguide. The calculated phase effective index of this mode is in sync with those obtained from measurements. The analysis started by observing the effect of embedding the copper wires in two-, three- (isosceles position), and four-wire configurations. The waveguide with 4 mm core diameter is able to provide a terahertz guidance from 0.2 –1.0 THz, while 3 mm is 0.3 – 1.0 THz. Further, the low attenuation, less than 0.5 cm−1 can be obtained from 0.4 – 1 THz for 4 mm waveguide and 0.5 – 1 THz for 3 mm waveguide. The coupling efficiency achieved for 3 mm core diameter waveguide is in the range of 50% - 62%, and 56 - 60% for 4 mm core diameter waveguide. The group velocity dispersion is less than |5| ps. THz-1. cm-1 for the frequency range of 0.4 – 1 THz for the 3 mm core diameter waveguides and close-to-zero dispersion within 0.4 - 1 THz range for the 4 mm core diameter.
