Performance analysis of highly sensitive PCF sensor for drug detection

Modelling of a single core photonic crystal fiber (PCF) based sensor has been performed to detect illegal drug namely ketamine, amphetamine, and cocaine. A single core PCF has been developed with two different sized circular air holes in two layers. With the aim of achieving low confinement losses and high sensitivity elliptical air holes into the cladding and a larger circular air hole in core region have been incorporated that is to be filled with drug samples. Silica serves as the background material. PCF based bio sensor typically act upon varying refractive index of PCF. These changes affect the propagation of light inside the fibre. When light propagate through core, change in optical property of core results into interaction of drug molecule with light. The suggested fiber has been performing at mid infrared region, generated a wide effective area and relatively low confinement loss. So, the single core photonic crystal fiber-based sensor is an ideal approach for detection. The relative sensitivity values for amphetamine, ketamine and cocaine have been obtained 93.39%, 97.22% and 93.34% consecutively at 1.8 µm operating wavelength and has almost negligible confinement loss so the proposed design of bio sensor is appropriate for sensing application of illicit drugs.