An intra-cavity Raman laser using synthetic single-crystal diamond

Abstract

Low birefringence synthetic single-crystal diamond was used as a Raman laser medium inside a Q-switched Nd:YVO(4) laser. A maximum average output power of 375 mW was achieved at a wavelength of 1240 nm and a repetition rate of 6.3 kHz. This equates to a conversion efficiency of 4% from the diode laser to the first Stokes component at 1240 nm. Optical losses within the diamond (approximately 1% per single pass) limited the performance and are currently the main barrier to the demonstration of an efficient CW diamond Raman laser.

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

“…The higher upper bound given by this technique compared to the ISO approach results from its lower accuracy, the effect of the coatings (these had some visible damage as a result of the laser experiments which may have contributed to the measured absorption), and the effect of any scattered light absorbed in the mount. Even so, an absorption coefficient of <0.006cm 1 is a significant improvement on the sample used in [8,9] where an absorption coefficient of ~0.03cm 1 was measured using the same apparatus. However, laser calorimetry is not, in general, sensitive to scatter, which may be a significant fraction of the overall loss if the absorption is small [23]: a different measurement technique would be required to determine this and hence the total loss.…”

“…Recently, the use of high optical quality, single-crystal, synthetic diamond as a Raman material in external cavity [3][4][5][6] and intracavity [7][8][9] configurations has been demonstrated -made possible by the progress in diamond chemical vapour deposition (CVD) [10,11]. Diamond has a large Raman gain (64cm/GW at = 532nm [12] and between 12.5cm/GW [13] and 16.6cm/GW [5] at = 1064nm), broad transparency (0.23-2.5µm and >7µm [14]) and a large Raman shift (1332cm 1 [15]).…”

CVD-diamond external cavity nanosecond Raman laser operating at 1.63 µm pumped by 1.34 µm Nd:YAP laser

“…As the pump sources, mostly neodymium or ytterbium doped lasers generating at fundamental frequency or higher harmonics were used. The Raman laser operation at different first Stokes wavelengths was demonstrated: 275 nm [16], 573 nm [17,18], 1193 nm [19], and 1240 nm [20][21][22][23].…”

CVD-diamond external cavity Raman laser operating at 1632 nm

“…As a synthetic diamond prepared by a CVD method become available, Raman laser operation in intra-or external-cavity resonator configuration, and under continuous or pulsed pumping was investigated. Generation of the 1 st Stokes wavelength at 573 nm [1,2], 1193 nm [3], and 1240 nm [4,5] was demonstrated.…”