16 W continuous-wave Raman laser using low-loss synthetic diamond

Abstract

Low-birefringence ( n<2x10 6 ), low-loss (absorption coefficient <0.006cm1 at 1064nm), single-crystal, synthetic diamond has been exploited in a CW Raman laser. The diamond Raman laser was intracavity pumped within a Nd:YVO 4 laser. At the Raman laser wavelength of 1240nm, CW output powers of 1.6W and a slope efficiency with respect to the absorbed diode-laser pump power (at 808nm) of ~18% were measured. In quasi-CW operation, maximum on-time output powers of 2.8W (slope efficiency ~24%) were observed, resulting in an absorbed diode-laser pump power to the Raman laser output power conversion efficiency of 13%. References and links ©2011 Optical Society of America

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

“…Recent developments in chemical vapour deposition growth have led to material with low birefringence and low absorption through the minimisation of the dislocation density and nitrogen impurities respectively [20,21]. This has made the intracavity use of diamond in solid-state lasers more practical -as a heat spreader [28,29] and in Raman lasers [11,[15][16][17][18].…”

“…For diamond, this figure of merit is over two orders of magnitude higher than for KGW based on typically available lengths. Such advantages, coupled to the recent improvements in the optical quality of synthetic single crystal diamond [11,20,21] have motivated the recent interest in diamond for Raman lasers. In this paper the properties of diamond will be experimentally assessed in the context of continuous-wave intracavity Raman lasers, using KGW as a standard for comparison.…”

“…After reflection from the dichroic mirror (10) the amplified probe emission reached a photo detector (12). The signals from detectors (11) and (12) were analysed using a digital oscilloscope (13). Attenuation was used to ensure that the ratio of the signals from detector (11) and detector (12) was equal to one when the sample (5) was not pumped.…”

“…Lee et al have demonstrated even higher continuous-wave powers in the visible by intracavity frequency conversion: 4.3W at the second harmonic of the first Stokes wavelength [9] and up to 5.3W via sum frequency mixing of the Stokes and fundamental fields [10]. Using diamond as the Raman laser material, the highest continuouswave output power achieved to date is 1.6W at the first Stokes wavelength [11].…”

“…As a result there is considerable interest in the use of diamond as a Raman laser material, both in pulsed [15][16][17] [11,18]. This work is motivated by the exceptional thermal properties of diamond [19] and enabled by the recent development of high optical quality synthetic diamond grown by chemical vapour deposition [11,20,21]. In this paper, modern synthetic single-crystal diamond will be compared with KGW, a representative conventional Raman laser crystal.…”