[Show abstract][Hide abstract] ABSTRACT: We report for the first time on the efficient continuous-wave and mode-locked laser operation of a diode-pumped Yb:Gd0.64Y0.36VO4 laser. cw output power of 855mW with a slope efficiency of 45% with respect to the absorbed pump power was demonstrated for the 2.1%-doped crystal. In mode-locked regime with SESAM as passive shutter pulses as short as 100fs were obtained.
Applied Physics B 12/2006; 85(4):581-584. · 1.78 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We analyze the physical processes in the nonlinear wavelength conversion stages of a recently demonstrated red–green–blue (RGB) laser source, which generated
of average power in each color. The system is based on an infrared femtosecond mode-locked laser and contains a frequency doubler, a parametric generator, a parametric amplifier, and two sum-frequency conversion stages. It does not require any resonant cavities, external laser amplifiers, or nonlinear crystals operated at elevated temperatures; therefore it appears to be more practical than other previously demonstrated RGB laser sources. However, the optimization of the overall system is nontrivial, because pump depletion, birefringence, and temporal walk-off in the first conversion stages lead to spatial and temporal distortion of the interacting beams in the subsequent nonlinear conversion stages. This leads to the interaction of spatially and temporally distorted beams in the later conversion stages. By using a numerical simulation of the nonlinear conversion processes based on a Fourier-space method in one temporal and two transverse spatial dimensions, we can fully take into account these effects. We analyze and discuss the physical effects in the different conversion stages and describe the optimization of the overall system performance.
Journal of the Optical Society of America B 01/2006; 23(2):265-275. · 2.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The luminescence decay times are measured taking into account reabsorption for KY(WO4)2:Yb(KYW:Yb) crystals with atomic concentrations of active ions from 0.2% to 30%. The radiative lifetime of Yb3+ ions was measured to be 233 mus. The cw output power of 1.46 and 1.62 W was achieved with the slope efficiency 52% and 47% for Yb:KYW lasers with the atomic concentration of Yb3+ ions equal to 10% and 30%, respectively. Using a semiconductor mirror with a saturable absorber (SESAM) in the passive mode-locking regime, pulses of duration 194 and 180 fs were obtained at wavelengths of 1042 and 1039 nm for crystals with Yb3+ concentrations equal to 10% and 30%, respectively, the average output power being 0.63 and 0.75 W.
[Show abstract][Hide abstract] ABSTRACT: A diode-pumped Yb:YVO4 laser has been passively mode locked for the first time, to our knowledge. 120 fs pulses with an average output power of 300 mW and a peak power as high as 14.5 kW are obtained by use of a semiconductor saturable-absorber mirror for passive mode locking. The optical spectrum has a 10 nm bandwidth (full width at half-maximum) and is centered at 1021 nm.
[Show abstract][Hide abstract] ABSTRACT: We report on the efficient CW, Q-switched and mode-locked laser operation of a diode-pumped Yb:YVO4 laser. CW output power of 1W with slope efficiency of 59 % with respect to absorbed pump power was demonstrated.
[Show abstract][Hide abstract] ABSTRACT: Using a high average power passively mode-locked thin disk laser we generated 24-fs pulses at an average power of 32 W and a pulse repetition rate of 57 MHz through nonlinear fiber compression.
[Show abstract][Hide abstract] ABSTRACT: We present a red-green-blue laser source with average powers of 8 W in the red, 23 W in the green, and 10.1 W in the blue. The entire pump power for the nonlinear conversion stages is provided by a single laser oscillator without any amplifier stages. Our system does not require any synchronized cavities, and all nonlinear crystals except one are critically phase matched at room temperature.
[Show abstract][Hide abstract] ABSTRACT: We demonstrate a multi-watt RGB laser source, using a frequency doublet, a two-stage parametric generator, and two sum frequency mixers. We do not require any synchronously pumped parametric oscillator or a laser amplifier.
Lasers and Electro-Optics, 2004. (CLEO). Conference on; 06/2004
[Show abstract][Hide abstract] ABSTRACT: We demonstrate a synchronously pumped high-gain optical parametric oscillator with feedback through a fiber, using a passively mode-locked Yb:YAG thin-disk laser as a pump source. We obtain as much as 19-W average signal power at a wavelength of 1.45 microm in 840-fs pulses and 7.8 W of idler power at 3.57 microm. The repetition rate of the pulses is 56 MHz, and the transverse beam quality of the generated signal is M2 < 1.6.
[Show abstract][Hide abstract] ABSTRACT: With a passively mode-locked thin disk Yb:YAG laser we pumped a two-stage optical parametric generator producing ultrashort pulses with 11 W average power at 799 nm and 6 W at 1448 nm. Sum frequency mixing of the latter two wavelengths with residual 1030-nm light results in multi-watt output powers at 450 nm and 602 nm.
[Show abstract][Hide abstract] ABSTRACT: We report on passively mode-locked think disk lasers with up to 60 W average power, nonlinear pulse compression to 33 fs with 18 W average power, and a fiber-feedback parametric oscillator generating 15 W in the 1.5-mum region.
[Show abstract][Hide abstract] ABSTRACT: We demonstrate that nonlinear fiber compression is possible at unprecedented average power levels by use of a large-mode-area holey (microstructured) fiber and a passively mode-locked thin disk Yb:YAG laser operating at 1030 nm. We broaden the optical spectrum of the 810-fs pump pulses by nonlinear propagation in the fiber and remove the resultant chirp with a dispersive prism pair to achieve 18 W of average power in 33-fs pulses with a peak power of 12 MW and a repetition rate of 34 MHz. The output beam is nearly diffraction limited and is linearly polarized.
[Show abstract][Hide abstract] ABSTRACT: We report on experiments with high-power femtosecond pulses from a passively mode-locked thin disk Yb:YAG laser: nonlinear fiber compression to 33 fs with 18 W average power and a fiber-feedback parametric oscillator generating 15 W in the 1.5-μm region.
Lasers and Electro-Optics Europe, 2003. CLEO/Europe. 2003 Conference on; 07/2003
[Show abstract][Hide abstract] ABSTRACT: We demonstrate a passively mode-locked diode-pumped thin-disk Yb:YAG laser generating 810-fs pulses at 1030 nm with as much as 60 W of average output power (without using an amplifier). At a pulse repetition rate of 34.3 MHz, the pulse energy is 1.75 microJ and the peak power is as high as 1.9 MW. The beam quality is close to the diffraction limit, with M2 < 1.1.
[Show abstract][Hide abstract] ABSTRACT: We demonstrate a synchronously pumped high-gain OPO with feedback through a fiber, using an Yb:YAG thin disk laser as pump source. We obtained 15.5 W average signal power at a wavelength of 1.45 μm in 630-fs pulses.
[Show abstract][Hide abstract] ABSTRACT: We discuss the latest achievement on passively mode-locked high-power lasers, delivering tens of watts of average power in sub-picosecond pulses. The most promising concept is that of the passively mode-locked thin disk Yb:YAG laser which can so far generate up to 50 W of average power in sub-picosecond pulses.
[Show abstract][Hide abstract] ABSTRACT: By combining a passively mode-locked high-power laser with a large mode area holey fiber for nonlinear compression, we generated 33-fs pulses with 18-W average power. The output beam is linearly polarized and close to diffraction-limited.
[Show abstract][Hide abstract] ABSTRACT: We demonstrate what is to our knowledge the first passively mode-locked thin-disk Yb:KY(WO(4))(2) laser. The laser produces pulses of 240-fs duration with an average power of 22 W at a center wavelength of 1028 nm. At a pulse repetition rate of 25 MHz, the pulse energy is 0.9microJ , and the peak power is as high as 3.3 MW. The beam quality is very close to the diffraction limit, with M(2)=1.1 .