Anisotropic thermal analyses of a high efficiency Tm:YAP slab laser and its intra-cavity pumping for Ho lasers

12.7 W intra-cavity pumped Ho:YAG laser with near-diffraction-limited beam quality

We demonstrated a compact and efficient Ho:YAG slab laser intra-cavity pumped by a Tm:YLF slab laser for the first time. In the Tm:YLF laser operation, the maximum power of 32.1 W with optical-to-optical efficiency of 52.8% was obtained. In the intra-cavity pumped Ho:YAG laser operation, the output power of 12.7 W at 2122 nm was obtained. The beam quality factors M² in the vertical and horizontal directions were 1.22 and 1.11, respectively. The RMS instability was measured to be lower than 0.1%. To the best of our knowledge, this was the maximum power for the Tm-doped laser intra-cavity pumped Ho-doped laser with near-diffraction-limited beam quality.

Theoretical and experimental investigations on Nb2CTxMXene Q-switched Tm:YAP laser at 2μm for the nonlinear optical response

In this paper, the Nb₂CT_xMXene nanosheets were fabricated and the corresponding microstructures were investigated. The nonlinear optical response was illustrated by open aperture Z-scan and I-scan methods. The ground and the excited state absorption cross-sections of 2D Nb₂CT_xMXene were also investigated. As the saturable absorber (SA), the Nb₂CT_xMXene was applied in the passively Q-switched Tm:YAP laser. 1.96μs Q-switched pulses with 3.97 W peak power were achieved at the repetition frequency of 80 kHz. Further theoretical model was built by using the coupled rate equations in simulating the dynamic process of the passively Q-switched Tm:YAP laser. The numerical simulation results are fundamentally in agreement with the experimental results, which proves the Nb₂CT_xMXene can be a good potential nanomaterial for further optoelectronic applications.

Crystal growth, optical, thermal and piezoelectric properties of HoCa4O(BO3)3 crystal

High-quality crystals of HoCa4O(BO3)3 were grown by the Czochralski method. The optical, thermal and piezoelectric properties were investigated.

11 W YLF-based intra-cavity pumped Ho laser with near diffraction limited beam quality

We develop a fluoride-based intra-cavity pumped Ho laser for the first time, where the severe thermal lensing of the intra-cavity pumping mechanism can be compensated by the negative thermal-optical property of the YLiF₄ (YLF) host. A maximum output power of 11.3 W (π-pol) at 2062 nm, corresponding to a conversion efficiency of 28.2% from the incident diode laser to the Ho laser, was obtained with a power instability below 0.5% and a near diffraction limited beam quality with M² of 1.06 and 1.25 in the horizontal and vertical directions, respectively. These are the maximum power and the best beam quality for the reported compact intra-cavity pumped Ho lasers, to the best of our knowledge.