Maurizio Manzo
University of North Texas, USA
Title: Optical sensing based on micro-scale resonators
Biography
Biography: Maurizio Manzo
Abstract
The whispering gallery mode phenomenon has attracted many scientists since was discovered by Lord Rayleigh in the 20th century in the San Paul cathedral in London. The high-quality factor together with the micro-scale dimensions of the resonator is fundamental for sensor’s applications. The light trapped inside a micro-resonator travels through total internal reflection generating the whispering gallery modes (WGMs) or morphology dependent resonances (MDRs). The optical modes are highly sensitive to the morphology of the resonator and any external event that induces a change in size, shape, and index of refraction of the micro-resonator leads to a shift in its optical modes. Therefore, the induced WGMs shifts can be related to the applied external event. In most applications, the coupling between the light and the micro-resonator is made using a single mode optical fiber connected to one end to a tunable diode laser and connected to the other end to a photodiode; on the other hand, wireless coupling is used in measurements where cabling tends to be problematic; in this case, a dye doped micro-resonator which acts as a tiny laser is used.