Abstract
Generation of efficient frequency-double fiber-based continuous wave (cw) orange laser radiation at 590-nm by single-pass second harmonic generation (SHG) of 1180-nm high-power Raman fiber laser in two 20-mm long bulk periodically poled MgO doped lithium niobate (PP-MgO: LN) crystals arranged in series is reported. Single-pass SHG efficiency with a single 20-mm long crystal was limited by large linewidth of the fundamental laser source in comparison to the wavelength acceptance of the PP-MgO: LN crystal. With this configuration, 50-75% increase in SHG efficiency has been obtained. At 9.9-W of the 1180-nm Raman fiber laser, 1.2-W of cw orange laser radiation with power stability of ±1.2% recorded over a one-hour period has been achieved.
