Speaker: Shawana Tabassum, ECpE Graduate Student
Advisor: Ratnesh Kumar and Liang Dong
Title: Nano-structure Based Optical Sensors Fabrication and Demonstration to Gas Sensing Applications
Abstract: We present three different nano-resonant structures (nanoposts, nanoholes etc.) fabricated on either bulk substrate or micron size tip of optical fiber for gas detection in visible or mid-infrared (IR) region of electromagnetic spectrum. The three nanostructure-based gas sensing techniques are based on the detection of surface plasmon resonance (SPR) wavelength shifts, guided mode resonance (GMR) wavelength shifts, and Rayleigh anomaly (RA) mode intensity variations. The SPR and GMR based sensors operate in the visible region of light spectrum. Later, we also integrate a heater with the GMR-based fiber-tip sensor to realize a reusable gas sensor having tunable sensor recovery time. The RA-based sensor is realized by solvent-casting of chalcogenide (ChG) glass to work as mid-IR optical resonator.