Thulium-Doped Silica fibers with enhanced fluorescence lifetime and their application in ultrafast fiber lasers

0499885 - ÚFE 2019 RIV CH eng J - Článek v odborném periodiku
Cajzl, Jakub - Peterka, Pavel - Kowalczyk, M. - Tarka, J. - Sobon, G. - Sotor, J. - Aubrecht, Jan - Honzátko, Pavel - Kašík, Ivan
Thulium-Doped Silica fibers with enhanced fluorescence lifetime and their application in ultrafast fiber lasers.
FIBERS. Roč. 6, č. 3 (2018), č. článku 66. ISSN 2079-6439
Grant CEP: GA ČR(CZ) GA17-20049S
Grant ostatní: COST ACTION(XE) MP1401- AFLASER
Institucionální podpora: RVO:67985882
Klíčová slova: Energy transfer * Cross-relaxation * Fiber lasers
Obor OECD: Optics (including laser optics and quantum optics)

In this work we report on the thulium-doped silica-based optical fibers with increased fluorescence lifetime of the F-3(4) level thanks to the modification of the local environment of thulium ions by high content of alumina. The determination of the cross-relaxation energy-transfer coefficients from the measurements of the fluorescence lifetimes of the F-3(4) and H-3(4) energy levels of Tm3+ ions in the experimentally prepared optical fiber is provided as well. Preforms of optical fibers were prepared either by conventional solution-doping of Tm3+ and Al3+ ions or by dispersion-doping of Tm3+ ions with alumina nanoparticles. Optical fibers were characterized by means of Tm, Al, and Ge concentrations, refractive index profiles, optical spectral absorption and luminescence, and by time-resolved fluorescence spectroscopy. Highly aluminium-codoped thulium silicate optical fibers exhibited fluorescence lifetimes of over similar to 500 s with maximum value of 756 s, which means a fluorescence lifetime enhancement when compared to the thulium-doped fibers reported elsewhere. We show an application of the thulium-doped fiber in a compact all-fiber ring laser that is passively mode-locked by using graphene-based saturable absorber. The output pulsewidth and repetition rate were 905 fs and 32.67 MHz, respectively
Trvalý link: http://hdl.handle.net/11104/0292078