330 mJ single-frequency Ho:YLF slab amplifier

Abstract

We report on a double-pass Ho:YLF slab amplifier which delivered 350 ns long single-frequency pulses of up to 330 mJ at 2064 nm, with a maximum M2 of 1.5 at 50 Hz. It was end pumped with a diode-pumped Tm:YLF slab laser and seeded with up to 50 mJ of single-frequency pulses.

Analysis on preferential free running laser wavelength and performance modeling of Tm3+-doped YAP and YLF

“…Besides the applications introduced previously, another prominent application of Tm 3 -doped lasers is in-band pumping of holmiumdoped laser systems. As pointed out by Kim et al [15], the holmium 5 I 8 metastable level typically has a longer lifetime and a stronger emission cross section compared to the 3 F 4 level of thulium, indicating the saturation intensity of Ho 3 -doped laser materials is lower, thus providing more superior performance in Q-switched mode [16,17] or pulse energy amplifier systems [18][19][20]. However, the present commercially available laser diodes emitting around 1.9 μm, which is the pump wavelength for Ho 3doped lasers, have much lower brightness and efficiency in comparison with other standard diode-laser wavelengths [17].…”

“…For example, to pump Ho:YAG, 1.908 μm is the best pump wavelength, which can be obtained from Tm:YLF [22]. While for pumping of Ho:YLF, one should choose 1.94 μm which can be obtained from both Tm:YLF and Tm:YAP, or 1.89 μm, which can be obtained from Tm:YLF [18,19].…”

An efficient continuous-wave and Q-switched single-pass two-stage Ho:YLF MOPA system

“…To achieve hundreds of mJ pulse energies, extremely high pump powers, cryogenic cooling systems of Ho:YLF crystals, long cavity laser configurations and dry air atmosphere are needed. Furthermore, in the case of high energy level systems, pulse repetition frequency is limited to a single Hz [7,8]. Such solutions are often presented as huge laser systems, difficult to be commercialized.…”

2-μm wavelength, high-energy Ho:YLF chirped-pulse amplifier for mid-infrared OPCPA

“…These limitations can be mitigated using powerful pump lasers emitting at 2-μm wavelength thereby reducing the photon ratio mismatch and allowing the use of highly nonlinear non-oxide crystals such as ZGP [13]. While the technology of such lasers, based on Q-switched Ho:YLF (or Ho:LuLiF) and Ho:YAG, is very mature for generating high-energy nanosecond pulses [14][15][16][17][18][19][20], amplification of few picosecond pulses from such systems to the multi-tens of mJ has not been reported. In this Letter, we report on a compact and stable laser system operating at 2-μm wavelength, delivering ∼10 ps duration optical pulses with up to 39-mJ output energy at 100-Hz repetition rate.…”