Characterization of Single-Crystal Synthetic Diamond for Multi-Watt Continuous-Wave Raman Lasers

A continuous-wave diamond Raman laser is demonstrated with an output power of 5.1 W at 1217 nm. This Raman laser is intracavity pumped by a side-pumped Nd:YLF rod laser: a 43-fold brightness enhancement between the Nd:YLF and diamond Raman lasers is observed, with the M
²
beam propagation factor of the diamond Raman laser measured to be <; 1.2. Although higher output powers are demonstrated in a similar configuration using KGd(WO
₄
)
₂
(KGW) as the Raman laser material (6.1 W), the brightness enhancement is much lower (2.5 fold) due to the poorer beam quality of the KGW Raman laser (M
²
<; 6). The Raman gain coefficient of single-crystal synthetic diamond at a pump wavelength of 1064-nm is also measured: a maximum value of 21±2 cm/GW is returned compared to 5.7±0.5 cm/GW for KGW at the same wavelength.