Laser recrystallization and inscription of compositional microstructures in crystalline SiGe-core fibres
2016 (English)In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 7, 13265Article in journal (Refereed) Published
Glass fibres with silicon cores have emerged as a versatile platform for all-optical processing, sensing and microscale optoelectronic devices. Using SiGe in the core extends the accessible wavelength range and potential optical functionality because the bandgap and optical properties can be tuned by changing the composition. However, silicon and germanium segregate unevenly during non-equilibrium solidification, presenting new fabrication challenges, and requiring detailed studies of the alloy crystallization dynamics in the fibre geometry. We report the fabrication of SiGe-core optical fibres, and the use of CO2 laser irradiation to heat the glass cladding and recrystallize the core, improving optical transmission. We observe the ramifications of the classic models of solidification at the microscale, and demonstrate suppression of constitutional undercooling at high solidification velocities. Tailoring the recrystallization conditions allows formation of long single crystals with uniform composition, as well as fabrication of compositional microstructures, such as gratings, within the fibre core.
Place, publisher, year, edition, pages
Nature Publishing Group, 2016. Vol. 7, 13265
Atom and Molecular Physics and Optics
IdentifiersURN: urn:nbn:se:kth:diva-196389DOI: 10.1038/ncomms13265ISI: 000385927200001ScopusID: 2-s2.0-84992315950OAI: oai:DiVA.org:kth-196389DiVA: diva2:1050360
QC 201611282016-11-282016-11-142016-11-28Bibliographically approved