Hollow core photonic crystal fiber for chemical identification in terahertz regime

A new kind of rectangular hollow core photonic crystal fiber (HC-PCF) has been proposed and analyzed in the terahertz regime to detect the chemical analytes. In this proposed HC-PCF a rectangular shaped air hole is used in the core and circular air holes are introduced in the cladding. Full vectorial finite element method (FEM) with perfectly matched layer (PML) boundary condition is used to investigate the guiding characteristics of the proposed HC-PCF. Our proposed PCF exhibits a high relative sensitivity and extremely low confinement loss for different chemical analytes. In addition, this proposed chemical sensor offers high birefringence, high numerical aperture and almost zero flattened dispersion over a wide frequency range. This proposed fiber can be used in chemical sensing as well as various polarization maintaining terahertz applications.