Luminescence and laser properties of RE-doped silica optical fibers: The role of composition, fabrication processing, and inter-ionic energy transfers

Controlled phase-separation effect for enhanced optical refrigeration in yttrium-aluminosilicate glasses

“…27 The high field strength of rare earth elements, in mixture with the covalent bonds of SiO 2 network, correlates a preferential linking to non-bridging oxygens (NBO). 42 This leads to the formation of Yb–O–Yb clusters, promoting cooperative relaxation and drastically decreasing ASC efficiency. At higher concentration, phase-separated droplets of rare-earth oxide are formed.…”

Demonstration of laser cooling in a novel all oxide GAYY silica glass

“…Although this increases the concentration of rare earths, the high phonon energy environment of the oxide glass also limits the concentration at which quenching occurs 18 , 19 . This leads to reduced quantum efficiency through non-radiative interactions and lifetime shortening of the radiative emission from the excited manifold 18 . Thus, high phonon energy and detrimental aggregation of Yb ions encountered at high doping in oxide glasses remain challenging, making it necessary to improve material purification and increase the concentration of the rare earth, principally Yb ions, to improve cooling efficiency.…”

“…This has resulted in an increase in the silica concentration quenching limit from 10 25 ions/m 3 to 10 [26][27] ions/m 3 16,17 . Although this increases the concentration of rare earths, the high phonon energy environment of the oxide glass also limits the concentration at which quenching occurs 18,19 . This leads to reduced quantum efficiency through non-radiative interactions and lifetime shortening of the radiative emission from the excited manifold 18 .…”

Luminescence lifetime of Er-doped silica optical fibers: the role of composition and fabrication processing

“…Silica glass suffers from several drawbacks, such as high phonon energy and low RE ion solubility, both of which hinder luminescence properties. To overcome these deficiencies, pure silica glass needs to be co-doped with a suitable modifier, such as Al2O3, which locally acts to increase RE ion solubility and form a beneficial low-phonon environment 3,4 .…”