Phys.org April 26, 2024
In the field of optical sensing, Whispering-Gallery-Mode (WGM) microresonators have emerged as promising candidates, offering the advantages of high sensitivity, high resolution, and small footprint. However, conventional sensing methods, which rely on tracking changes in a single mode, have a limited dynamic range of measurement. Researchers at Washington University developed a theoretical framework that offers comprehensive analytical insights for multimode-sensing techniques and demonstrated an optical WGM barcode technique that enabled simultaneous monitoring of the patterns of multiple modes that could provide over-FSR (Free spectral range) tracking with high resolution. They assessed the theoretical limits of measurement resolution and dynamic range, independent of specific sensing system and estimation algorithm. Comparative analysis of the single-mode sensing and multimode sensing confirmed the improvement in resolution and dynamic range achievable through the barcode technique based on the multimode spectrum. According to the researchers their work lays the foundation for developing a high-resolution sensor with superior sensitivity across a drastically expanded dynamic range… read more. TECHNICAL ARTICLE (conf paper)
… the innovative barcode technique provides detailed information about the sensor’s surroundings… Credit: Yang Lab