CC BY
17LS-I-2
Rare earth doped selenide glasses as 5-6 ^m laser materials
S.E.Sverchkov1, B.I.Denker1, B.I.Galagan1, V.V.Koltashev3, V.G.Plotnichenko3, G.E.Snopatin2, M.V.Sukhanov2, A.P.Velmushov2, M.P.Frolov4, P.Fjodorow45, S.O.Leonov46
1- Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilova str.38, Moscow, Russia
2- Devyatykh Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, Tropinina
49, Nizhny Novgorod, Russia
3- Dianov Fiber Optics Research Center, Russian Academy of Sciences, Vavilova 38, Moscow, Russia 4- Lebedev Physical Institute, Russian Academy of Sciences, Leninsky prosp. 53, 19991, Russia 5- Institute for Combustion and Gas Dynamics — Reactive Fluids, University of Duisburg-Essen, Lotharstr.
1, 47057 Duisburg, Germany 6- Bauman Moscow State Technical University, 2nd Baumanskaya str. 5, 105005, Moscow, Russia
Chalcogenide glasses for long attracted attention as potential hosts for mid-infrared lasers for their high infrared transparency and low multiphonon quenching rate of mid-infrared rare earth transitions. Nevertheless, the uncontrollable impurities in the glasses impeded the creation of such lasers. The latest achievements in fabrication of ultrapure rare earth doped chalcogenide glasses and fibers have made the creation of such lasers realistic. Samples of Ge36GasSe59 glass activated by Ce3+, Pr3+ or Tb3+ ions (up to 1020 cm-3) were prepared. All these ions have 5-6 ^m radiative transitions (Fig.1, Table 1) ending on the ground level with luminescence quantum yield in the investigated glass >80%.
Wavelength, nm Absorbed pump energy, mJ
Fig.1. Mid-IR emission of Ce3+, Pr3+ and Tb3+ ions Fig.2. Mid-IR Ce3+ laser action in selenide glass
In the lasing experiments several pulsed solid-state lasers (Table 1) were used for bulk glass samples pumping. The Tb-doped fiber was pumped by CW holmium fiber laser. Fig. 2 shows an example oi mid-infrared Ce3+ laser input-output characteristics.
Table 1. Pump and lasing wavelengths of Ce3+, Pr3+ and Tb3+ in Ge36Ga5Se59 glass.
Active ion and transition Pump source (wavelength in p,m) Configuration Lasing wavelengths,
Ce3+, 2Fy/2^2F5/2 Fe:ZnSe laser (4.08) 1-3 cm long bulk 5.1-5.52
Pr3+, 3H5^3H4 Er:glass laser (1.54) 5.5-5.9
Cr:Tm:Ho YAG laser (2.08) 5.6-5.8
Tb3+, 7F5^7F6 Er:YAG laser (2.94) 4.9-5.5
Ho: fiber laser (1.98) 20 cm long fiber 5.37-5.39
The investigations showed, that the attained purity level and optical quality of the doped selenide glasses enables to obtain laser action at 5-6 ^m microns in all three investigated active ions.
Funding. Russian Foundation for Basic Research (18-29-20079); Russian Academy of Sciences (Program No. 5); Russian Science Foundation (20-79-00155).
