AUTHOR=Feng Chaoyu , Yu Changqiu , Hu Yuchi , Chang Jian , Hou Pei , Li Hai , Guo Ying TITLE=Dual hollow sphere optical resonator for simultaneous detection of acoustic and magnetic fields JOURNAL=Frontiers in Physics VOLUME=Volume 13 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2025.1539959 DOI=10.3389/fphy.2025.1539959 ISSN=2296-424X ABSTRACT=This study introduces a novel dual-parameter sensor for simultaneous acoustic and magnetic field detection. The sensor employs a dual-hollow-sphere-shaped optical microresonator coupled with a fiber taper and integrated with a Terfenol-D sheet. Experimental results demonstrate best sensitivities of 4.24 mPa/√Hz for acoustics and 5.16 nT/√Hz for magnetic fields within a 0.1–2 MHz detection range. Notably, the sensor can detect both parameters independently at different frequencies without mutual interference. This innovative design offers a promising approach for non-destructive testing of the state of the high-voltage transmission lines.