A design of whispering gallery mode based biosensors

• Main Author: Xu Wenting
• Other Authors: Luan Feng
• Format: Final Year Project
• Language: English
• Published: 2015
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/62026
• Institution: Nanyang Technological University

Laser can be confined inside the resonator to travel around its perimeter by way of total internal reflections. These special waves are called whispering gallery mode (WGM). The light wave has high value of Q factor since it travels almost perfectly around the smooth surface. WGM biosensor is highly sensitive miniature device that is based on the high-Q WGM. Recently, metallic diffraction grating is demonstrated as an effective and robust coupler to the WGM resonator. Although its stable performance has made it a suitable candidate for implementation of bio-sensing, the metallic diffraction grating coupler still suffers from several defects that limit its use in practical applications. The development of this project is based on the metallic diffraction grating biosensor and the main idea is “packaging”. For the purpose of compact arrangement and stable coupling, we make the grating and the resonator as a whole set for sensing activities. Since the fiber and grating are both small and fragile, we use capillary tubes to achieve the goal.