Femtosecond Laser Engraving of Deep Patterns in Steel and Sapphire.

Femtosecond laser engraving offers appealing advantages compared to regular laser engraving such as higher precision and versatility. In particular, the inscription of deep patterns exhibits an increasing interest in industry. In this work, an optimization protocol based on constraining overlap ratio and scan number is demonstrated.

Efficient and high-throughput ablation of platinum using high-repetition rate radially and azimuthally polarized sub-picosecond laser pulses.

A highly productive ablation process of 100 nm thick platinum films with a processed area rate of up to 378 cm/min is presented using radially and azimuthally polarized laser beams. This was achieved by developing a laser amplifier generating 757 fs long laser pulses at a maximum average power of 390 W and a repetition rate of 10.6 MHz with adjustable polarization states, i.

μJ-level Raman-assisted fiber optical parametric chirped-pulse amplification.

We experimentally demonstrate the amplification of chirped pulses in a fiber optical parametric chirped pulse amplifier up to 1 μJ. This high energy level originates from combined Raman and parametric processes in a specially designed solid core photonic bandgap fiber. Output pulses are recompressed up to 560 fs.

Ultra-broadband fiber optical parametric amplifier pumped by chirped pulses.

We numerically and experimentally demonstrate ultra-broadband fiber optical parametric amplification in a microstructured fiber pumped by stretched short pulses. The chirped pump pulse induces a temporally spread spectral gain suitable for optical parametric chirped pulse amplification in fibers. Numerical simulation shows ~45  dB flat gain with more than 70 nm bandwidth, allowing sub-35 fs pulse amplification around 1 μm with reduced gain narrowing.

Amplification of ultra-short optical pulses in a two-pump fiber optical parametric chirped pulse amplifier.

We demonstrate with realistic numerical simulations that fiber optical parametric chirped pulse amplification is able to amplify ultra-short optical pulses. Such amplifiers driven by two-pump waves can amplify pulse bandwidth twice as large as the one of a single pump configuration. We show that pulses as short as 50 fs can be directly amplified.