title: Tuning of optical resonances in asymmetric microtube cavities.
abstract: We tune optical resonances in rolled-up SiO/SiO(2) microtube cavities by gradually modifying the tube structure through asymmetrical postdeposition of SiO(2). Spectral blueshifts followed by redshifts of the resonant modes are observed in a thin-walled microtube (tube-I), which is attributed to a competition between shape deformation and effective increase of tube wall thickness. In contrast, only a monotonic redshift is detected when asymmetrical deposition is performed on a thick-walled microtube (tube-II). Distinct wavelength-dependent tuning was revealed in both kinds of tubes. Numerical calculations based on perturbation theory are carried out to explain and confirm the experimental results.
authors.affiliation: Institute for Integrative Nanosciences, Leibniz-Institut für Festkörper-und Werkstoffforschung Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany.
authors.forename: Libo
authors.initials: L
authors.lastname: Ma
authors.forename: Suwit
authors.initials: S
authors.lastname: Kiravittaya
authors.forename: Vladimir A Bolaños
authors.initials: VA
authors.lastname: Quiñones
authors.forename: Shilong
authors.initials: S
authors.lastname: Li
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Mei
authors.forename: Oliver G
authors.initials: OG
authors.lastname: Schmidt