Millijoule pulse energy high repetition rate femtosecond fiber chirped-pulse amplification system

Abstract

We report on an ytterbium-doped fiber chirped-pulse amplification (CPA) system delivering millijoule level pulse energy at repetition rates above 100 kHz corresponding to an average power of more than 100 W. The compressed pulses are as short as 800 fs. As the main amplifier, an 80 microm core diameter short length photonic crystal fiber is employed, which allows the generation of pulse energies up to 1.45 mJ with a B-integral as low as 7 at a stretched pulse duration of 2 ns. A stretcher-compressor unit consisting of dielectric diffraction gratings is capable of handling the average power without beam and pulse quality distortions. To our knowledge, we present the highest pulse energy ever extracted from fiber based femtosecond laser systems, and a nearly 2 orders of magnitude higher repetition rate than in previously published millijoule-level fiber CPA systems.

Yb-doped large-pitch fibres: effective single-mode operation based on higher-order mode delocalisation

“…18,19 Furthermore, these fibres are the basis of mJ-level femtosecond fibre amplifiers, which are routinely operated in state-of-the-art fibre chirped-pulse amplification systems. 20 The reproducible fabrication of this first VLMA-PCF design with its arrangement of tiny air holes (necessary for the effective single-mode operation of these few-mode fibres) is extremely challenging. This reproducibility issue results in a low yield, which increases the costs.…”

Compact Ultrafast Oscillators and High Performance Ultrafast Amplifiers Based on Ytterbium-Doped Fibers

“…The schematic setup of the high energy high average power fiber CPA system is shown in Fig. 4.10 [30]. It consists of a passively mode-locked Yb:KGW oscillator, a dielectric grating stretcher-compressor unit, an acousto-optical modulator used as pulse selector and two ytterbium-doped photonic crystal fibers both used in singlepass configuration as amplification stages providing an overall gain factor of approximately 25,000.…”

High-energy picosecond Nd:YVO4 slab amplifier for OPCPA pumping

“…3). The maximum achievable output energy could be increased by chirped pulse operation, reducing the B-integral, as implemented in [13]. This would, however, come at the expense Fig.…”