Multiresonator Imaging Sensor for the Aerial Parameters Detection

Anton V Saetchnikov,Andreas Ostendorf,Elina A Tcherniavskaia,Vladimir A Saetchnikov

doi:10.1109/jmass.2020.3033387

Abstract

Applicability of the whispering gallery mode sensor in the form of the multiresonator imaging device for the atmospheric-relevant parameters monitoring has been demonstrated. The sensor design and the appropriate techniques for sensing data collection have been discussed. The sensor performance has been numerically and experimentally studied on examples of the temperature variation detection and the monitoring of small spherical microparticles ( <; 3 μm) that have been used to mimic the particulate contamination of the environment. The thermal sensitivity of the sensor on the level of 8.6 pm/°C has been experimentally demonstrated. The experimental results on the distinguishing of the microparticle concentrations (0.5% and 1%) via the wavelength sweeping technique and the results on the single particle detection under illumination at the fixed wavelength have been shown.

Highlights

The optical sensing techniques employing the laser light as a probe belong to the most efficient approaches for characterization of the changes in the physical and chemical parameters of the object under study
One of the most intensively researched optical sensing techniques arose from the resonance phenomenon of the whispering gallery modes (WGM) occuring in the microcavities [1]–[3]
According to the quasi-geometrical approximation the spectral position of each WGM with a polar mode number (m) in the microresonator of radius R follows the equation with neff standing for the effective refractive index

Summary

Introduction

The optical sensing techniques employing the laser light as a probe belong to the most efficient approaches for characterization of the changes in the physical and chemical parameters of the object under study. One of the most intensively researched optical sensing techniques arose from the resonance phenomenon of the whispering gallery modes (WGM) occuring in the microcavities [1]–[3]. The WGMs are formed in an optical ring resonator where the light is guided along the resonator’s periphery due to the multiple total internal reflections so that the returning wave starts to interfere with itself. The mechanism for the detection of the external parameter variations is based on the monitoring of the WGM spectral changes: the resonance frequency shift, linewidth broadening, and mode splitting [4]. The materials for the cavities fabrication include glass, polymers, quartz, etc

Methods

Results

Conclusion