Thermal analysis and CW laser operation at 1.998 µm in end pumped Tm:YAP lasers

We report on thermal analysis and a continuous wave (CW) laser operation at (1.998µm) of end pumped Tm: YAP cylindrical laser rod. The Tm: YAP laser rod is pumped at a wavelength of 1.064 µm emitting from Nd: YAG laser source. A 3W incident pump power is used to generate a maximum laser output of 700 mW, representing 18% slope efficiency. The power of thermally induced lens in Tm:YAP laser rod is numerically analyzed and validated experimentally. The focal lengths of the thermally induced lens are directly measured using Shack-Hartmann wavefront sensor. We have detected blue up-conversion fluorescence emission before laser operation at 1.998 µm. The obtained experimental results were in good agreement with the numerical calculations. Full Text: PDF ReferencesI. F. Elder, J. Payne, "Diode-pumped, room-temperature Tm:YAP laser", Applied Optics 36 (33), 8606 (1997) CrossRef Y. Li, B. Yao, Y. Wang, Y. Ju, G. Zhao, Y. Zong, J. Xu, "High efficient diode-pumped Tm:YAP laser at room temperature", Chinese Opt. Lett. 5 (5), 286 (2007). DirectLink H. Ni, S. C. Rand, "Avalanche upconversion in Tm:YALO3", Opt. Lett. 16 (8), 1424 (1991). CrossRef Z. G. Wang, C. W. Song, Y. F. Li, Y. L. Ju, Y. Z. Wang, "CW and pulsed operation of a diode-end-pumped Tm:GdVO4 laser at room temperature", Laser Phys. Lett. 6 (2), 105 (2009). CrossRef Baoquan Yao, Yi Tian, Wei Wang, Gang Li, Yuezhu Wang, "Analysis and compensation of thermal lens effects in Tm:YAP lasers", Chinese Opt. Lett. 8 (10), 996 (2010). CrossRef F. Cornacchia, D. Parisi, C. Bernardini, M. Toncelli, "Efficient, diode-pumped Tm3+:BaY2F8 vibronic laser", Opt. Expr. 12 (9), 1982 (2004). CrossRef Xiaojin Cheng, Mi Fan, Jiandong Cao, Jianhua Shang, "Research on the thermal effect and laser resonator of diode-pumped thin-slab Tm:YAP lasers", Optik 176, 32 (2019). CrossRef W. Koechner, Solid-state Laser Engineering, Springer, (2013). DirectLink https://www.crytur.cz DirectLink http://www.laserlabcomponents.com/ DirectLink R. M. El-Agmy, N.AlHosiny, "2.31 [micro sign]m laser under up-conversion pumping at 1.064 [micro sign]m in Tm3+:ZBLAN fibre lasers", Elect. Lett. 46 (13), 936 (2010). CrossRef R. M. El-Agmy, N. M. Al-Hosiny, "870 mW blue laser emission at 480 nm in a large core thulium doped ZBLAN fiber laser", Laser Phys. 20 (4), 838 (2010). CrossRef R. M. El-Agmy, N. M. Al-Hosiny, "Power scaling of end-pumped Nd:YLF lasers, modeling and experiments", Optik 140, 584 (2017). CrossRef R. M. El-Agmy, N. Al-Hosiny, "Thermal analysis and experimental study of end-pumped Nd: YLF laser at 1053 nm", Photonic sensors 7 (4), 329 (2017). CrossRef S. C. Tidwell, J. F. Seamans, M. S. Bowers, A. K. Cousins, "Scaling CW diode-end-pumped Nd:YAG lasers to high average powers", IEEE J. Quantum Electron. 28, 997 (1992). CrossRef P. J. Hardman, W. A. Clarkson, G. J. Friel, M. Pollnau, D. C. Hanna, "Energy-transfer upconversion and thermal lensing in high-power end-pumped Nd:YLF laser crystals", IEEE Journal of Quantum Electronics 35, 647 (1999). CrossRef

A 70 W thulium-doped all-fiber laser operating at 1940 nm

An all-fiber thulium-doped fiber laser operating at a wavelength of 1940 nm is reported. A maximum output continuous-wave power of 70.7 W with a slope efficiency of 59%, determined with respect to the absorbed pump power, was demonstrated. The laser delivered almost a single-mode beam with a beam quality factor of < 1.3.Full Text: PDF ReferencesM. N. Zervas and C. A. Codemard, "High Power Fiber Lasers: A Review", IEEE J. Sel. Top. Quantum Electron. 20, 0904123 (2014). CrossRef D. J. Richardson, J. Nilsson, and W. A. Clarkson. "High power fiber lasers: current status and future perspectives [Invited]", J. Opt. Soc. Am. B 27, B63 (2010). CrossRef J. Swiderski, A. Zajac, and M. Skorczakowski, "Pulsed ytterbium-doped large mode area double-clad fiber amplifier in MOFPA configuration", Opto-Electron. Rev. 15, 98 (2007). CrossRef M. Eckerle et al. "High-average-power actively-modelocked Tm3+ fiber lasers", Proc. SPIE 8237, 823740 (2012). CrossRef J. Swiderski, D. Dorosz, M. Skorczakowski, and W. Pichola, "Ytterbium-doped fiber amplifier with tunable repetition rate and pulse duration", Laser Phys. 20, 1738 (2010). CrossRef P. Grzes and J. Swiderski, "Gain-Switched 2-μm Fiber Laser System Providing Kilowatt Peak-Power Mode-Locked Resembling Pulses and Its Application to Supercontinuum Generation in Fluoride Fibers", IEEE Phot. J. 10, 1 (2018). CrossRef S. Liang et al. "Transmission of wireless signals using space division multiplexing in few mode fibers", Opt. Express 26, 6490 (2018). CrossRef J. Swiderski, M. Michalska, and P. Grzes, "Broadband and top-flat mid-infrared supercontinuum generation with 3.52 W time-averaged power in a ZBLAN fiber directly pumped by a 2-µm mode-locked fiber laser and amplifier", Appl. Phys. B 124, 152 (2018). CrossRef F. Zhao et al. "Electromagnetically induced polarization grating", Sci. Rep. 8, 16369 (2018). CrossRef J. Sotor et al. "Ultrafast thulium-doped fiber laser mode locked with black phosphorus", Opt. Lett. 40, 3885 (2015). CrossRef M. Olivier et al. "Femtosecond fiber Mamyshev oscillator at 1550 nm", Opt. Lett. 44, 851 (2019). CrossRef J. Swiderski and M. Michalska, "Over three-octave spanning supercontinuum generated in a fluoride fiber pumped by Er & Er:Yb-doped and Tm-doped fiber amplifiers", Opt. Laser Technol. 52, 75 (2013). CrossRef C.Yao et al. "High-power mid-infrared supercontinuum laser source using fluorotellurite fiber", Optica 5, 1264 (2018). CrossRef J. Swiderski and M. Maciejewska, "Watt-level, all-fiber supercontinuum source based on telecom-grade fiber components", Appl. Phys. B 109, 177 (2012). CrossRef O. Traxer and E. X. Keller, "Thulium fiber laser: the new player for kidney stone treatment? A comparison with Holmium:YAG laser", World J. Urol., 1-12 (2019). CrossRef M. Michalska, et al. "Highly stable, efficient Tm-doped fiber laser—a potential scalpel for low invasive surgery", Laser Phys. Lett. 13, 115101 (2016). CrossRef R. L. Blackmon et al. "Thulium fiber laser ablation of kidney stones using a 50-μm-core silica optical fiber", Opt. Eng., 54, 011004 (2015). CrossRef A. Zajac et al. "Fibre lasers – conditioning constructional and technological", Bull. Pol. Ac.: Tech. 58, 491 (2010). CrossRef C. Guo, D. Shen, J. Long, and F. Wang, "High-power and widely tunable Tm-doped fiber laser at 2 \mu m", Chin. Opt. Lett. 10, 091406 (2012). CrossRef F. Liu et al. "Tandem-pumped, tunable thulium-doped fiber laser in 2.1 μm wavelength region", Opt. Express 27, 8283 (2019). CrossRef H. Ahmad, M. Z. Samion, K. Thambiratnam, and M. Yasin, "Widely Tunable Dual-Wavelength Thulium-doped fiber laser Operating in 1.8-2.0 mm Region", Optik 179, 76 (2019). CrossRef N. M. Fried, "Thulium fiber laser lithotripsy: An in vitro analysis of stone fragmentation using a modulated 110‐watt Thulium fiber laser at 1.94 µm", Lasers Surg. Med. 37, 53 (2005). CrossRef N. M. Fried, "High‐power laser vaporization of the canine prostate using a 110 W Thulium fiber laser at 1.91 μm", Lasers Surg. Med. 36, 52 (2005). CrossRef E. Lippert et al. "Polymers Designed for Laser Applications-Fundamentals and Applications", Proc. SPIE 6397, P639704 (2006). CrossRef N. Dalloz et al. "High power Q-switched Tm3+, Ho3+-codoped 2μm fiber laser and application for direct OPO pumping", Proc. SPIE 10897, 108970J (2019). CrossRef N. J. Ramírez-Martinez, M. Nunez-Velazquez, A. A. Umnikov, and J. K. Sahu, "Highly efficient thulium-doped high-power laser fibers fabricated by MCVD", Opt. Express 27, 196 (2019). CrossRef T. Ehrenreich et al. "1-kW, All-Glass Tm:fiber Laser", Proc. SPIE 7580, 758016 (2010). DirectLink L. Shah et al. "Integrated Tm:fiber MOPA with polarized output and narrow linewidth with 100 W average power", Opt. Express 20, 20558 (2012). CrossRef H. Zhen-Yue, Y. Ping, X. Qi-Rong, L. Qiang, and G. Ma-Li, "227-W output all-fiberized Tm-doped fiber laser at 1908 nm", Chin. Phys. B 23, 104206 (2014). CrossRef