Photobleaching of photodarkening in ytterbium doped aluminosilicate fibers with 633 nm irradiation

Photodarkening of Infrared Irradiated Yb3+-Doped Alumino-Silicate Glasses: Effect on UV Absorption Bands and Fluorescence Spectra

“…From Figure 4 it can be noted that P1 band depends on Yb 3+ concentration which is in accordance with [8]. ODC creation [13], activation of different color centers (CC) types [14] or increased phonon-electron coupling [15]. However, in Figure 4 there seems to exist a critical concentration of around 1 wt% of Yb 3+ ions above which the non linear growth is observed for the irradiated samples: thus the nonlinear growth of P1 after the irradiation should be mainly related to the Yb 3+ -Yb 3+ pairs interaction influenced by UV light.…”

“…As the consequence, it is possible that the last part of the stretched exponential curve (much longer than characteristic time "τ") shows smaller PD rate since defects of a different type were created. These defects can be on higher energy level as suggested by limited bleaching at 633 nm [14] and have lower impact on PD being the absorption tail blue-shifted. In addition, the total PD loss can increase due to increase of specific CC type although the total number of CC remains the same due to CC type conversion.…”

Ultra-broadband infrared luminescence of Bi-doped thin-films for integrated optics

“…As P O2 decreases, Bi species will be reduced. Moreover, the utilization of high power laser in PLD could induce the reduction of doping active ions [21]. Earlier studies suggested that BIA of low valence state could be generated by laser irradiation [22].…”

Simultaneous effects of photo- and radio- darkening in ytterbium-doped aluminosilicate fibers

“…The measurement bench is based on a pump-probe scheme [4,7,10] with contra-propagating pump (977 nm, 230 mW) and visible probe (633 nm, a few mW). Customized wavelength division multiplexers (OZ-optics) are used for coupling pump and probe lights into the fiber under test (FUT).…”

“…Excess optical losses are induced by external ionizing radiations (radiodarkening or RD), but also, possibly, due to the pump itself (photo-darkening, PD). PD and RD of YDF have been already well characterized [1][2][3][4][5][6][7][8][9][10][11][12], but by distinct communities. Possible interplay between PD and RD has neither been characterized nor modelled, though pumping and ionizing radiations should be at play simultaneously in some operation conditions, as in space-based applications.…”