{"title":"Analysis of splitting direction for coupling WGM resonators","authors":"Jianwei Wang, Jiapeng Sun, Yeshuai Song, Xulong Yang, Xinghua Yang, Yu Zhang, Zhihai Liu, Hanyang Li","doi":"10.1007/s00340-025-08501-3","DOIUrl":null,"url":null,"abstract":"<div><p>Opposite splitting directions in mode splitting are observed in whispering gallery mode resonators, composed of asymmetrically coupled bispheres. To interpret this phenomenon, we introduce a “virtual ellipsoid” model, which establishes a direct correlation between the optical behavior of bispheres and that of ellipsoidal resonators. The splitting characteristics, including intensity difference and wavelength separation, are systematically investigated through theoretical analysis and experimental validation. These findings demonstrate that the splitting direction is governed by the relative positions of the fundamental and azimuthal modes within the splitting peaks. Experimental results further confirm that an increase in the diameter of Sphere D<sub>2</sub> leads to a redshift in the resonant wavelength, attributed to the extended optical path in the whispering gallery mode. Additionally, we propose an optical barcode approach based on the transmission spectra to intuitively characterize the optical features of splitting peaks, offering potential applications in size measurement of microspheres or ellipsoids, as well as optical information identification.</p></div>","PeriodicalId":474,"journal":{"name":"Applied Physics B","volume":"131 7","pages":""},"PeriodicalIF":2.0000,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Physics B","FirstCategoryId":"4","ListUrlMain":"https://link.springer.com/article/10.1007/s00340-025-08501-3","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"OPTICS","Score":null,"Total":0}
引用次数: 0
Abstract
Opposite splitting directions in mode splitting are observed in whispering gallery mode resonators, composed of asymmetrically coupled bispheres. To interpret this phenomenon, we introduce a “virtual ellipsoid” model, which establishes a direct correlation between the optical behavior of bispheres and that of ellipsoidal resonators. The splitting characteristics, including intensity difference and wavelength separation, are systematically investigated through theoretical analysis and experimental validation. These findings demonstrate that the splitting direction is governed by the relative positions of the fundamental and azimuthal modes within the splitting peaks. Experimental results further confirm that an increase in the diameter of Sphere D2 leads to a redshift in the resonant wavelength, attributed to the extended optical path in the whispering gallery mode. Additionally, we propose an optical barcode approach based on the transmission spectra to intuitively characterize the optical features of splitting peaks, offering potential applications in size measurement of microspheres or ellipsoids, as well as optical information identification.
期刊介绍:
Features publication of experimental and theoretical investigations in applied physics
Offers invited reviews in addition to regular papers
Coverage includes laser physics, linear and nonlinear optics, ultrafast phenomena, photonic devices, optical and laser materials, quantum optics, laser spectroscopy of atoms, molecules and clusters, and more
94% of authors who answered a survey reported that they would definitely publish or probably publish in the journal again
Publishing essential research results in two of the most important areas of applied physics, both Applied Physics sections figure among the top most cited journals in this field.
In addition to regular papers Applied Physics B: Lasers and Optics features invited reviews. Fields of topical interest are covered by feature issues. The journal also includes a rapid communication section for the speedy publication of important and particularly interesting results.