Silica and germanate-based rare-earth doped glasses for fiber lasers

0503231 - ÚFE 2019 RIV US eng C - Conference Paper (international conference)
Kamrádek, Michal - Kašík, Ivan - Peterka, Pavel - Aubrecht, Jan - Podrazký, Ondřej - Honzátko, Pavel - Mrázek, Jan - Kubeček, V.
Silica and germanate-based rare-earth doped glasses for fiber lasers.
Fiber Lasers and Glass Photonics: Materials through Applications. Bellingham: SPIE, 2018 - (Taccheo, S.; Mackenzie, J.; Ferrari, M.), č. článku 106832L. Proceedings of SPIE, 10683. ISBN 978-151061892-3. ISSN 0277-786X.
[Conference on Fiber Lasers and Glass Photonics - Materials through Applications. Strasbourg (FR), 22.04.2018-26.04.2018]
R&D Projects: GA ČR(CZ) GA17-20049S
Institutional support: RVO:67985882
Keywords : germanate-based glass * mid-infrared spectral region * Fiber lasers
OECD category: Optics (including laser optics and quantum optics)

Since an extension of spectral region from near-infrared to mid-infrared covered by fiber lasers belongs to ambitions of today's research, germanate-based glasses have been proposed, fabricated and their optical properties studied. Glass samples were prepared by Modified Chemical Vapor Deposition method and by conventional glass melting processes. Fabricated preforms suitable for fiber drawing were optically characterized by refractive index and absorption spectra measurements. A limit of rare earths doping of GeO2-based glasses without phase separation was found comparable to SiO2-based glasses (thousands of ppm). Preforms prepared by Modified Chemical Vapor Deposition contained only up to 29 mol. % of GeO2 in core, although pure GeO2 glass layers were deposited. This effect caused transparency limitation of such materials to 2-2.5 mu m. Implementing of effective drying processes during GeO2-based glass conventional melting lead to decrease of residual OH- content to the level comparable with optical silica glass HOQ 310. The shift of infrared transmission edge of bulk GeO2-based conventionally prepared glasses to longer wavelengths towards to 5 mu m was observed. These facts support the idea of potential use of GeO2-based glass matrices for fiber lasers operating in mid-infrared region
Permanent Link: http://hdl.handle.net/11104/0295052