Self‐Collimation and Slow Light‐Based Refractive Index Sensor with a Large Detection Range

Abstract

AbstractIn this study, a refractive index sensor based on self‐collimation and slow light is presented which operates in the Mid‐IR range (4 µm < λ < 4.133 µm). Here, the square and hexagonal arrays are merged as the background platform and the sensing area, respectively to provide self‐collimation and slow light properties. Three sensors based on slow‐light and self‐collimation are presented in detail which provide Q‐factor, sensitivity, and detection range of 227, 104 nm RIU−1, and 1–1.7, respectively in the best case. Furthermore, the sensor design based on self‐collimation and photonic bandgap phenomena in the background platform and the sensing area, respectively is presented with a single detection unit. The presented sensors are capable of gas or liquid detection with refractive indices in the range of 1–2 with enhanced Q‐factor and sensitivity of over 620 and 123, respectively.