ENGINEERING OPTICAL METAMATERIAL FOR ENHANCED AND SELECTIVE SENSING AT MID-IR SPECTRA

Abstract

This thesis presents novel engineering and fabrication techniques for enhanced and selective sensing of biochemicals and gases at mid-IR by optical metamaterials. Firstly, a fractal approach for self-similar inclusion into metamaterial building block for high quality factor and multispectral performance for sensing applications is explored. Then, sensing utilizing phonon-plasmon coupled modes at mid-IR, e.g., absorption induced transparency(AIT) accompanied by their temperature dependence studyis reported. Later, development of robust platformfor refractory metamaterial based emitter in CMOS compatible nondispersive infrared (NDIR) gas sensor and thermal stress related issues are comprehensively addressed. Furthermore, a hybrid polymer-metamaterial absorber platform for significant miniaturization of inert gas and volatile organic compound (VOC) sensor with high sensitivity (down to ppm range) and selectivity is experimentally demonstrated.It provides insights into various aspects of metamaterial based sensing at mid-IR which will directly translate into reality on the emerging flexible-wearable sensing platform and dynamically tunable and sensitive 2D material devices.