Thermal lens study of energy transfer in Yb^3+/Tm^3+-co-doped glasses

Abstract

Energy transfer (ET) and heat generation processes in Yb(3+)/Tm(3+)-co-doped low-silica calcium-aluminosilicate glasses were investigated using thermal lens and photoluminescence measurements. Stepwise ET processes from Yb(3+) to Tm(3+), with excitation at 0.976 mum, produced efficient emission in the mid-infrared range at around 1.8 mum, with high fluorescence quantum efficiency (~0.50) and relatively low thermal loading (</=0.42). An equation was deduced for the description of the thermal lens results which provided the absolute value of the ET efficiency and optimal Tm3+ concentration that result in population of the 1.8 mum Tm(3+) emitting level. These results suggest that the studied co-doped system would be a promising candidate for the construction of high-power diode-pumped solid-state lasers in the mid-infrared range, which are especially important for the purpose of medical procedures.

Photothermal Study of Two Different Nanofluids Containing SiO2 and TiO2 Semiconductor Nanoparticles

“…As a matter of fact, this technique has proved to be one of the most sensitive methods. For instance, it was recently used for determination, with high sensitivity, of the linear absorption coefficient spectrum of water [17]; the effect of nanoparticles on the fluorescence quantum efficiency of dye lasers [21]; the interaction between emitter ions [22]; the effect of impurities on the optical properties of laser materials [23][24][25]; etc.…”

Spectroscopic investigation and heat generation of Yb^3+/Ho^3+ codoped aluminosilicate glasses looking for the emission at 2 μm

“…Their optical quality was shown to be very good, which was verified by observing the scattering level of a He-Ne laser tuned at 632.8 nm. The experimental setup and characterization of the prepared samples were performed as explained in our previous works [29,30,42].…”

“…Recently, we demonstrated that Yb 3 ∕Tm 3 -codoped lowsilica calcium aluminosilicate (LSCAS) glasses generate a highly efficient emission around 1.8 μm with a relatively low thermal loading [30]. The explanation to this finding was the high ET efficiencies from Yb 3 to Tm 3 ions and that the LSCAS matrix combines the superior thermo-mechanical properties of an oxide glass with a phonon energy of the order of 800 cm −1 , an intermediate value compared to silicates (∼1100 cm −1 ) and nonoxide (∼500 cm −1 ) glasses.…”

Emission decay and energy transfer in Yb/Tm Y-codoped fibers based on nano-modified glass

“…For Yb/Tm system the efficiency of the ET from Yb 3+ to Tm 3+ ions reaches 50% [7]. The typical lifetimes for the 3 F4 level of Tm 3+ vary from 200 to 650 μs, and for the 2 F5/2 level of Yb 3+ from 470 to 830 μs depending on the host composition [4,[8][9][10].…”