We report on experimental results on a high power, all-fibred, linearly polarized, mode-locked laser at 1.03 μm. The laser generates pulses of 40 ps wide at a repetition rate of 52 MHz, exhibiting 12 kW peak power. Dispersion in optical fibres is controlled to obtain both high power and narrow spectral linewidth. The average output power reached is 25 W with a spectral linewidth of 380 pm and a near diffraction limit beam (M<sup>2</sup> < 1.2). This laser is an ideal candidate for applications like IR spectroscopy, where high peak power and narrow linewidth are required for subsequent wavelength conversion.
We report on a high-power ultra-short fiber laser for thin film solar cells micromachining. The laser is based on Chirped
Pulse Amplification (CPA) scheme. The pulses are stretched to hundreds of picoseconds prior to amplification and can
be compressed down to picosecond at high energy. The repetition rate is adjustable from 100 kHz to 1 MHz and the
optical average output power is close to 13 W (before compression). The whole setup is fully fibred, except the
compressor achieved with bulk gratings, resulting on a compact and reliable solution for cold ablation.
In this letter, we report on the study of a new all-fiber laser source suitable for coherent Doppler LIDAR use in the eyesafe
domain. The laser consists on a MOPA configuration where the Master Oscillator is a modulated ultranarrow (< 8
kHz) fiber laser. The optical amplifiers are also all-fibered and make use of a new Large Mode Area (LMA) index
pedestal fiber that is very effective in limiting the non-linear effects without quality degradation of the laser beam. The
amplified pulses have a maximum energy of 0.15 mJ for a duration of 340 ns at a repetition rate of 15 kHz. The average
output power of the laser is 2.5 W, free of Stimulated Brillouin Scattering and with a measured M<sup>2</sup> = 1.3.
We experimentally compared the co- and counter-propagative pumping scheme for the amplification of ultra-short
optical pulses. According to pumping direction we show that optical pulses with a duration of 75 fs and 100mW of
average output power can be obtained for co-propagative pumping, while pulse duration is never shorter than 400 fs
for the counter-propagative case. We show that the impact of non-linear effects on pulse propagation is different for
the two pumping configurations. We assume that Self Phase Modulation (SPM) is the main effect in the copropagative
case, whereas the impact of Stimulated Raman Scattering is bigger for the counter-propagative case.
Laser wind velocimeters work by monitoring the Doppler shift induced on the backscattered light by aerosols that are present in the air. Recently there has been a growing interest in the scientific community for developing systems operating at wavelengths near 1.5 μm and based on all-fibre lasers configuration. In this paper, we propose a new all-fibre laser source that is suitable for Doppler velocimetry in aircraft safety applications. The all-fibre laser has been specifically conceived for aircraft safety application. Our prototype has a conveniently narrow linewidth (9 kHz) and is modulated and amplified through an all fibre Master Oscillator Power Amplifier (MOPA) configuration. According to the measurements, we performed the final characteristics of the laser consist in a maximum peak power of 2.7 kW and an energy of 27 μJ energy per pulses of 10 ns at 30 kHz repetition rate. The only limiting factor of these performances is the Stimulated Brillouin Scattering.
Midterm (1 - 1000s) stability of the traveling-wave Er-doped fiber ring laser has been experimentally studied as a function of laser parameters: the pump power, the doped fiber length and type, the total laser cavity length, polarization control, and the exit coupler ratio. In all cases the total cavity length over ten meters resulted in a multi-wavelength generation with the comb central wavelength, defined by a 1.12 GHz-band tunable Fabry-Perot filter with a 3.1 THz free spectral range. We have found that the key parameters defining the laser stability are the cavity length and the out-coupling ratio, while the polarization control seems not very important for our multi-wavelength regime. Output power variations are less than 0.02dB on a 10 min interval were obtained.