We have recently developed an industrial laser platform emitting in the non-conventional range around 976 nm. This 15 W continuous wave spatially single mode linearly polarized fiber laser can be forced to work in narrow line width or single frequency configuration. Its frequency doubling at 488 nm can be used to replace argon gas laser technology in many applications. We have studied the second harmonic generation of our source to verify its suitability with several industrial application needs in terms of efficiency, temporal stability and noise level.
We demonstrate an Ytterbium-doped fiber laser system generating high energy pulses at the non-conventional
wavelength of 977 nm. An actively Q-switched master fiber oscillator delivers 1.2 W of average power in 12 ns pulses at
82 kHz of repetition rate. This pulsed fiber source is then amplified in an ultra-large core photonic crystal fiber amplifier
up to 71 W. Deducing the fraction of power contained in interpulse ASE, we obtained 0.7 mJ pulses at 977 nm, resulting
in a pulse peak-power of >55 kW. To the best to our knowledge, this system delivers the highest performances ever
demonstrated in this spectral window.
We report on the first experimental demonstration of high order harmonic generation in rare gases directly
from a high power Ytterbium doped fiber chirped pulse amplification system. The laser delivers 270 fs pulses
in the 30-100 μJ energy range at repetition rate varying from 100 kHz to 1 MHz. A proper focalization allows
reaching several 10<sup>13</sup>W/cm<sup>2</sup> in the gas jet. We have been able to produce and detect harmonics up to order 31
in Ar, Kr, and Xe at 100kHz repetition rate. Harmonic generation at 1 MHz is also demonstrated in Xe up to
We report the generation of high temporal quality high energy ultra-short pulses from a moderately non-linear fiber
chirped pulse amplifier. The system is based on a two amplification stages and delivers 270 fs pulses of 100 μJ energy at
a repetition rate of 300 kHz. The excellent temporal quality of the recompressed pulses, down to 1.1 the Fourier limit,
allows the production of ~ 340 MW of peak power. The fibre chirped pulse amplifier is design to compensate the nonlinear
phase shift accumulated throughout the amplifier stages by third order of dispersion provided by mismatched
temporal stretcher and compressor units.
In this contribution, we report on an 80-μm core diameter Yb-doped rod type photonic crystal fiber laser emitting up to 94W in CW regime when operating at 977nm, which is to our knowledge the highest output power ever achieved from a single-mode solid-state laser operating at this wavelength. Key parameters of ytterbium doped 3-level laser, such as transparency pump intensity, pump absorption saturation, and gain competition between three and four level laser operation are then discussed in the particular context of high power fiber laser operating at 977nm. Possible applications of the demonstrated source are then discussed.