Energy transfer efficiency from Cr^3+ to Nd^3+ in solar-pumped laser using transparent Nd/Cr:Y_3Al_5O_12 ceramics

We report energy transfer efficiency from Cr 3+ o Nd 3+ in Nd (1.0 at.%)/Cr (0.4 at.%) co-doped Y 3 Al 5 O 12 (YAG) transparent ceramics in the laser oscillation states. The laser oscillation has performed using two pumping lasers operating at 808 nm and 561 nm; the former pumps Nd 3+ directly to create the 1064 nm laser oscillation, whereas the latter assists the performance via Cr 3+ absorption and sequential energy transfer to Nd 3+ . From the laser output power properties and laser mode analysis, the energy transfer efficiency was determined to be around 65%, which is close to that obtained from the spontaneous Nd 3+ emission.