Efficient ~2 μm Tm^3+-doped tellurite fiber laser

Tm^3+/Ho^3+ codoped tellurite fiber laser

“…Rare earths are highly soluble in it, allowing high doping levels to be achieved [2]. The low phonon energy of tellurite glass means that it is transparent much further into the infrared than either silica or germanate glass (up to ϳ5 m) [3]. Several benefits are brought forth by its high refractive index ͑1.95-2.05͒: Fibers made from it can have a high numerical aperture (NA) and both absorption and emission cross sections are enhanced [4].…”

“…1 of [3], with the Tm 3+ /Ho 3+ codoped tellurite fiber used instead of the Tm 3+ singly doped tellurite fiber. The pump source for the tellurite fiber laser was a Er 3+ /Yb 3+ -doped silica fiber (INO, Canada) laser operating at multiple lasing peaks within the range of ϳ1570-1610 nm; the silica fiber laser was pumped by a 970 nm laser diode.…”

Index matching between passive and active tellurite glasses for use in microstructured fiber lasers: Erbium doped lanthanum-tellurite glass

“…Tellurite glasses are promising hosts for fiber lasers operating in the mid-IR [1][2][3]. They have low phonon energies, high refractive indices, high rare earth solubility, infrared transmission up to 5 µm and high gain per unit length [4].…”

High-efficiency ～2 μm laser in a single-mode Tm-doped lead germanate composite fiber

“…In the past decade, rapid progress has been made with the development of ∼2 μm Tm-doped fiber lasers. Compared with silica glass, multicomponent glass as a fiber host has several advantages, including a lower phonon energy, resulting in a wider IR transmission range, high rare earth solubility, resulting in high gain per unit length, and a larger absorption/emission cross section, and it has attracted considerable attention [6][7][8][9] . In particular, germanate glasses, which have not only better mechanical strength and chemical durability than fluoride glasses but also higher thermal stability than tellurite glasses for output scaling, are promising materials for realizing 2 μm fiber lasers.…”

“…(T g , glass transition temperature; T x , onset temperature of crystallization; CTE, coefficient of thermal expansion at 30°C-300°C). In-band/tandem pumping is becoming a popular scheme for exciting Tm 3þ ions owing to its high Stockes efficiency, low quantum defect, and low thermal loading, opening the prospect of high lasing efficiency and the potential for further power scaling [8,[22][23][24] . Thus, in this work, an Yb/Er co-doped single-mode fiber laser operating at 1590 nm was employed as the pump source.…”