Work

Ultra-sensitive active whispering gallery mode sensor in an optofluidic microcapillary with Vernier effect of coupled modes

Year: 2025

Type: article

Abstract: Ultrahigh sensitivity is achieved in an optofluidic microcapillary active sensor by utilizing the Vernier effect of coupled whispering gallery modes. A refractive index sensitivity of 2924 nm/RIU is obtained experimentally, which is 7 times higher than the sensitivity limit of a conventional whispering gallery mode sensor. By reducing the wall thickness of the microcapillary to decrease the difference of free spectral range of the coupled whispering gallery modes, further improvement in refractive index sensitivity can be as high as 48426 nm/RIU. This sensing strategy allows us to design a robust, easily fabricated ultra-sensitive optical sensor for microfluidic sensing applications.

Source: Optics Express

DOI: 10.1364/oe.554693

Authors: Biao Li, Liying Liu, Lei Xu

Institution: Fudan University

Language: English

Topic: Photonic and Optical Devices

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,270

Funders: National Natural Science Foundation of China, Doctoral Program Foundation of Institutions of Higher Education of China