Related Experiment Video
Updated: Jun 4, 2026

Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors
Published on: January 29, 2013
Thermostable refractive index sensors based on whispering gallery modes in a microsphere coated with poly(methyl
Nai Lin1, Lan Jiang, Sumei Wang
1Laser Micro/Nano Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China.
Abstract:
This study proposes a thermostable refractive index (RI) sensor consisting of a silica microsphere coated with a poly(methyl methacrylate) (PMMA) layer. The first-order and second-order whispering gallery modes (WGMs) of both TE and TM polarizations are considered theoretically. The layer thickness is carefully optimized to eliminate the thermal drift and enhance the RI sensitivity and detection limit. In various WGMs, at the thermostable thickness of the PMMA layer, the first-order TM mode corresponds to the highest sensitivity and the smallest detection limit. The theoretical predictions provide guidelines for the design and fabrication of thermostable RI sensors.

