A rectangular porous-core cyclic olefin copolymer fiber applied to generate a broadband spectrum in THz region

A rectangular porous-core cyclic olefin copolymer fiber is characterized as being a low loss waveguide with ultra-low flattened dispersion and high birefringence in THz region. In this work, in addition to calculating the optical characteristics of this waveguide, the coupled generalized nonlinear Schrodinger equation describing the supercontinuum generation process is numerically solved for it. The generated spectral width is significantly wider than those for most common supercontinuum sources. In addition, our simulation results indicate that when a linearly polarized input pulse of 13.8 MW peak power and 22 fs pulse width is launched into the assumed waveguide, new frequencies are generated at the confined x- and y-polarized modes. The simulation results exhibit the generation of a broadband THz spectrum ranging from 160 to 260 mu m at the output of the waveguide.