Cr4+ doped garnets: novel laser materials and non-linear saturable absorbers

Chromium-doped silica optical fibres: influence of the core composition on the Cr oxidation states and crystal field

“…Tunability in RE-doped fibre lasers is already well established [1], but is limited to few tens of nanometers due to the intrinsic narrowness of the RE optical transitions. Besides, bulk solid-state lasers materials, doped with chromium, such as Cr 4+ :YAG, have demonstrated very good results as broad-band gain media [2], and also as saturable absorbers [3,4]. Therefore, it is of great interest to develop transition metal (TM) ion-doped optical fibres in order to implement their optical properties (as amplifying media or saturable absorbers) into optical fibre-based devices and systems.…”

The Passively Q-switched Microchip Nd:YAG Laser Optimization for Rangefinder Applications

“…Such an approach bases on the fact that the precision of the experimental determination of the GSA cross-section σ a1 is higher than the one of ESA cross-section σ a2 . Indeed, as it follows from the data shown in Table II, the relative difference between the values of σ a1 obtained in [2,8] is equal to 1.7, whereas the corresponding difference for σ a2 is two times higher. It must be mentioned that the values of σ a2 obtained by us are essentially higher than the ones indicated in [2,3,8].…”

“…Indeed, as it follows from the data shown in Table II, the relative difference between the values of σ a1 obtained in [2,8] is equal to 1.7, whereas the corresponding difference for σ a2 is two times higher. It must be mentioned that the values of σ a2 obtained by us are essentially higher than the ones indicated in [2,3,8]. Probably it is caused by peculiarities of the absorption medium used in this realization of the Nd:YAG/Cr:YAG laser, particularly, by using of epitaxial Cr:YAG film, not a bulk crystal.…”

“…Because of the uncertainty of the σ a1 , σ a2 , all calculations in the present work were carried out for three different sets of values. Each set was determined by the value of σ a1 obtained in [2][3]8] and the cross-section σ a2 was determined by fitting of the experimental data for Nd:YAG/Cr:YAG laser (Table I). Such an approach bases on the fact that the precision of the experimental determination of the GSA cross-section σ a1 is higher than the one of ESA cross-section σ a2 .…”

Simulation of laser internal cavity length and refractivity dependence of self-mixing interference velometry

“…Calculations of SMI signal  and I with varying refractivity (n=1.526 [14] 1.666 [15] 1.771 [15] 1.933 [16] at wavelength 1064nm   ) are carried out on the hypothesis of laser cavity length L=10mm. indicate that cycle and asymmetry of SMI intensity and frequency are both independent of refractivity.…”