title: Sharp whispering-gallery modes in rolled-up vertical SiO2 microcavities with quality factors exceeding 5000.
abstract: Record high quality (Q) factors of 5400 in vertical microtube ring resonators operated in emission mode are demonstrated. This is achieved by rolling-up a differentially strained SiO2 layer. We also present a theoretical model to investigate the limit of the Q factor. This model especially includes the effect of interlayer voids in the rolled-up geometry, which is found to have a larger effect than scattering due to notches in the spiral shape.
authors.affiliation: Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, Dresden 01069, Germany. s.boettner@ifw-dresden.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Böttner
authors.forename: Shilong
authors.initials: S
authors.lastname: Li
authors.forename: Jens
authors.initials: J
authors.lastname: Trommer
authors.forename: Suwit
authors.initials: S
authors.lastname: Kiravittaya
authors.forename: Oliver G
authors.initials: OG
authors.lastname: Schmidt