Excited state absorption and laser emission from infrared laser dyes optically pumped at 532 nm

Publisher Website
Google Scholar
Abstract
Efficient near‐infrared dye laser emission has been achieved in the 838–923‐nm range by use of a frequency‐doubled Nd:YAG laser as the optical pump for various polymethine dyes. Experimental evidence of 1064‐nm quenching of the dye laser emission is reported. Strong excited state absorption (ESA) effects are observed for the dye IR‐140 at the 532‐nm pump wavelength. This excited state absorption results in an experimentally determined optimum pump power density of 50–60 MW/cm2 for maximum dye laser efficiency. Such excited state absorption may thus be a limiting factor in the power scaling of pulsed dye lasers.