Highly sensitive hollow core spiral fiber for chemical spectroscopic applications

A hollow core spiral shaped photonic crystal fiber is proposed and analyzed in this paper for various chemical identification by using terahertz spectrum. To identify the propagation characteristics as a sensor, finite element method based software with perfectly matched layer boundary condition is employed. The numerical results confirms that, the proposed sensor offers very high relative sensitivity of 93.5%, 92.9% and 90.7% for benzene, ethanol and water respectively for optimum geometric structure. Furthermore, very low confinement loss and large numerical aperture can be achieved from the single mode fiber simultaneously at terahertz regime. All air holes of the sensor are circular shaped which create the fiber more feasible and it may be fabricated without any complexity. So that, this sensor might be a part of various real life chemical sensing applications.