Open Access12 kW quasi-steady-state diamond Raman laser pumped by an M2 = 15 beam
Author(s) -
Sergei Antipov,
Alexander Sabella,
Robert J. Williams,
Ondřej Kitzler,
David J. Spence,
Richard P. Mildren
Publication year - 2019
Publication title -
optics letters/optics index
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.524
H-Index - 272
eISSN - 1071-2763
pISSN - 0146-9592
DOI - 10.1364/ol.44.002506
Subject(s) - optics , laser , materials science , raman laser , diamond , slope efficiency , laser beam quality , raman spectroscopy , amplifier , diode , raman scattering , energy conversion efficiency , laser pumping , optoelectronics , fiber laser , physics , laser beams , cmos , composite material
An external cavity diamond Raman laser with 1.2 kW output power is demonstrated for durations 7 times longer than the thermal lens time constant. An 83% slope efficiency and a 53% optical-to-optical efficiency were obtained for conversion from a 1.06 μm pump to the 1.24 μm first Stokes. The pump had an M 2 of 15, demonstrating that efficiency is maintained at the highest levels even when using exceptionally poor quality pumps. We show that a measured decrease in the output beam quality factor from M 2 =2.95 to M 2 =1.25 as power increased is evidence for thermal lens development in the diamond. The results foreshadow development of continuous-wave kilowatt-class lasers or amplifiers based on single diamond elements and pumped efficiently by lasers having poor spatial coherence such as line-narrowed diode laser arrays.