36-W diode-pumped continuous-wave 1319-nm Nd:YAG ceramic laser

High-stability, high-beam-quality, and pulse-width-tunable 1319 nm laser system for VISAR applications in high-power laser facilities

A high-energy, high-beam-quality, and pulse-width-tunable Nd:YAG laser system, pumped by vertical cavity surface emitting laser arrays and laser diodes, is demonstrated and applied to a velocity interferometry system for any reflector (VISAR) application in a high power laser facility. A multistage multipass amplification structure is used to fully extract the amplifier energy and obtain a high-energy pulse. The temporal waveform is compensated to provide a square waveform, with a flatness less than 8% (peak-to-peak value). The peak power is greater than 100 kW with a frequency-doubling efficiency of 25% for a 50 ns pulse width. The laser operates as a single shot with 1-5 Hz repetition frequency and 0.7% rms energy stability.

Passively Q-switched Nd:YAG ceramic laser with V(3+):YAG saturable absorber at 1357 nm

1357 nm single-wavelength continuous-wave and passively V(3+):YAGQ-switched Nd:YAG ceramic crystal lasers have been experimentally demonstrated for the first time to our knowledge. The output power of the continuous-wave laser was as high as 2.4 W under the incident pump power of 14.8 W. The corresponding optical to optical efficiency was about 16.2% and the slope efficiency was about 18.6%. The Q-switched laser remained single-wavelength output with a maximum average output power of 628 mW at the incident pump power of 12.4 W. The corresponding pulse width was 21 ns and the repetition frequency was 15 kHz.

Continuous-wave yellow-green laser at 0.56 μm based on frequency doubling of a diode-end-pumped ceramic Nd:YAG laser

We present what is, to the best of our knowledge, the first report on yellow-green laser generation based on the frequency doubling of the 1.1 μm transitions in Nd:YAG ceramics. By employing an 885 nm diode laser as the end-pumping source and a lithium triborate crystal as the frequency doubler, the highest continuous wave output powers of 1.4, 0.5, and 1.1 W at 556, 558, and 561 nm are achieved, respectively. These result in optical-to-optical efficiencies of 6.9%, 2.5%, and 5.4% with respect to the absorbed pump power, respectively.

12.45 W wavelength-locked 878.6 nm laser diode in-band pumped multisegmented Nd:YVO₄ laser operating at 1342 nm

A multisegmented Nd:YVO4 laser operating at 1342 nm that is in-band pumped by a wavelength-locked 878.6 nm laser diode is reported here. We achieve an output power of 12.45 W at 1342 nm for an absorbed pump power of 35.6 W, corresponding to an optical-to-optical efficiency of 34.9% and a slope efficiency of 36.1%. To the best of our knowledge, it is the highest optical-to-optical efficiency of Nd:YVO4 lasers operating at 1342 nm with an output power more than 10 W.

Diode-side-pumped Nd:YLF laser emitting at 1313 nm based on DBMC technology

Efficient lasers operating in the 1.3 μm band are of interest in the health industry for frequency conversion to the visible spectral region and for Raman shifting to the eye-safe 1.5 μm region. In this work, we demonstrate for the first time, to our knowledge, a side-pumped Nd:YLiF(4) laser emitting at 1.3 μm. An output power of up to 14.9 W was obtained at 1313 nm with 54 W of absorbed pump power, representing 27.7% optical efficiency and a slope efficiency of 45%.

Continuous-wave tri-wavelength operation at 1064, 1319 and 1338 nm of LD end-pumped Nd:YAG ceramic laser

We demonstrated a laser-diode (LD) end-pumped continuous-wave (CW) tri-wavelength Nd:YAG ceramic laser operating at 1064, 1319 and 1338 nm. For the 1064 nm laser, one of the Nd:YAG polished end faces was used as the output coupler. As references, Nd:YVO(4) and Nd:YAG crystal lasers were also investigated under the same structure. We found that the maximum output power came from Nd:YAG ceramic which was 1.74 W, corresponding an optical conversion efficiency of 16.3%. Using a three mirror cavity, we realized efficient multi-wavelength operation at (4)F(3/2)-(4)F(11/2) and (4)F(3/2)-(4)F(13/2) transitions for Nd:YAG ceramic, simultaneously. The maximum output power was 3.2 W, which included 1064, 1319, and 1338 nm three wavelength, and the optical conversion efficiency was 30%.

1319 nm and 1338 nm dual-wavelength operation of LD end-pumped Nd:YAG ceramic laser

In this paper, we demonstrate the efficient 1.3 um dual-wavelength operation of LD end-pumped Nd:YAG ceramic laser. With a plano-concave cavity, a maximum continuous-wave dual-wavelength output power of 5.92 W is obtained under an incident pump power of 20.5 W, giving a slope efficiency of 30.3% and an optical-optical conversion efficiency of 29.0%. With Co(2+):LaMgAl(11)O(19) crystal as the saturable absorber, the passively Q-switched dual-wavelength operation is achieved for the first time to our knowledge. The maximum passively Q-switched average output power is 226 mW, the minimum pulse width is 15 ns, and the highest pulse repetition rate is 133 kHz.

Laser-diode pumped 40-W Yb:YAG ceramic laser

We demonstrated a high-power continuous-wave (CW) polycrystalline Yb:YAG ceramic laser pumped by fiber-pigtailed laser diode at 968 nm with 400 mum fiber core. The Yb:YAG ceramic laser performance was compared for different Yb(3+) ion concentrations in the ceramics by using a conventional end-pump laser cavity consisting of two flat mirrors with output couplers of different transmissions. A CW laser output of 40 W average power with M(2) factor of 5.8 was obtained with 5 mol% Yb concentration under 120 W incident pump power. This is to the best of our knowledge the highest output power in end-pumped bulk Yb:YAG ceramic laser.

Passively Q-switched dual-wavelength laser output of LD-end-pumped ceramic Nd:YAG laser

We reported a dual-wavelength laser with a ceramic Nd:YAG as laser material and Cr:YAG as frequency selector and saturable absorber. Continuous-wave output power was achieved to be as high as 6.19 W at 1052 nm. With Cr:YAG, the laser has dual-wavelength at 1052 and 1064 nm. The shortest pulse width, maximum pulse energy and highest peak power were 4.8 ns, 103.2 microJ, and 21.5 kW. This pulsed laser is possible to be used as a new source to generate terahertz radiation.