Design of a Terahertz Alcohol Sensor Using a Steering-Wheel Microstructured Photonic Crystal Fiber

摘要

In this paper, we design a novel photonic crystal fiber (PCF) chemical sensor wherein the cladding structure is made of a steering-wheel (SW)-shaped large non-circular air-hole. In this PCF, we introduce the rectangular air holes in the core and they are filled with any one of the analytes, namely, water, ethanol and benzene. We use the full-vectorial finite element method (FEM) to optimize the structural parameters. Based on the numerical results, we find that the proposed sensor exhibits a high relative sensitivity of 92.8%, 93.2% and 93.4% for water, ethanol and benzene, respectively, at THz. Furthermore, we study the various optical characteristics of the proposed PCF, namely, birefringence, effective area and numerical aperture (NA).