Comparison of parameters of q-switching saturable absorbers estimated by different models and the impact of accuracy of input data on the results of the estimation

Transparent cobalt‐doped yttrium aluminum garnet (Co2+:YAG) ceramics—An innovatory fast saturable absorber

“…Nevertheless, we noticed that the absorption cross sections of thin films of Co,Si:YAG with concentrations (mole fractions) in the range from 0.0002 to 0.0054 grown on YAG and Er,Yb:YAG substrates by means of the isothermal liquid‐phase epitaxy (LPE) dipping technique were varied between 3·10 −19 to 8·10 −19 cm 2 17 . In Co 2+ :YAG crystal with 2 at.% Co concentration grown by the Czochralski method, the value of the parameter is evaluated to be 8.6·10 −20 cm 2 18 . It should be remembered that the differences between concentrations of Co dopants in the above‐mentioned materials (ceramic, thin films, and crystal) are substantial.…”

“…17 In Co 2+ :YAG crystal with 2 at.% Co concentration grown by the Czochralski method, the value of the parameter is evaluated to be 8.6•10 −20 cm 2 . 18 It should be remembered that the differences between concentrations of Co dopants in the above-mentioned materials (ceramic, thin films, and crystal) are substantial. We presume that our results, that is, absorption cross sections of Co 2+ :Y 3 Al 5 O 12 ceramics between 5•10 −19 to 7•10 −19 cm 2 , are promising and comparable to those in literature.…”

Diode-side-pumped, passively Q-switched Yb:LuAG laser

“…The results of the experiments and calculations are summarized in Table 1. We used here the generalized model of passive Q-switching taking into account the excited state absorption effect in a saturable absorber [19][20][21]. We assumed for Cr:YAG a crystal ground-state absorption cross section s GSA ¼8.7 Â 10 À 19 cm 2 and an excited-state absorption cross section s ESA ¼2.2 Â 10 À 19 cm 2 [19].…”

“…These have to deliver energies of several dozens of mJ in the Q-switching regime. It is well known that efficient, high-energy operation in the Q-switching mode requires high gain and results in high fluencies inside the cavity [17][18][19][20][21]. In the Q-switching regime, efficient extraction in the case of Yb oscillators (72% of energy in the free-running regime as demonstrated in [11]) is possible despite the limitation imposed by a quasi-III-level scheme.…”

Variable energy, high peak power, passive Q-switching diode end-pumped Yb:LuAG laser

“…Yb:YAG and Cr:YAG), the laser giant pulse action develops inside the cavity and enables the efficient extraction of a significant part of the energy by means of the out-coupling mirror. The method of optimizing Q-switched lasers [14][15][16] can also be widened in the case of quasi-III-level gain media, especially for the case of short (compared to gain medium lifetime), repetition periods [3,19,22]. The measure of quality in the Q-switching regime is the extraction efficiency, i.e.…”