EU-Funded Kilowatt-class Ultrafast Laser Achieves Milestone

Collaborators on the EU-funded LAMpAS (high throughput laser structuring with multiscale periodic feature sizes for advanced surface functionalities) project have reportedly reached the target parameters of a kilowatt-class ultrafast laser. TRUMPF developed the pulsed laser, which in tests exceeded 1.5 kW of average optical power and operated at gigawatt-class peak power, with fundamental mode beam quality at a near-infrared wavelength of 1 μm.

A demonstrator system will be integrated into a machine designed for industrial laser micro-machining of larger square-meter-size surfaces within the LAMpAS project.

The LAMpAS project is an initiative of the Photonics Public Private Partnership. It began in 2019 with a grant of €5.1 million ($5.74 million) under the EU’s Horizon 2020 program. The project will increase the potential for laser structuring for the design of recently functionalized surfaces, increasing efficiency, flexibility, and productivity.

According to the Community Research and Development Information Service of the European Commission, it relies on the development of a high-power ultrashort-pulse laser system, as well as strategies and concepts for beam supply to be realized by combining the characteristics of direct laser interference patterning and polygon scanner processing laser technologies.

Further, the project aims to develop laser structuring technology at affordable costs and to design newly functionalized surfaces by enhancing the efficiency, flexibility, and productivity of processes based on the development of a high-power ultrashort-pulse laser system together with advanced optical concepts for high-throughput materials processing.

The thin-disk multipass amplifier module developed by TRUMPF. As part of the LAMpAS project, a team has realized the target parameters of a kilowatt-class ultrafast laser system. The pulsed laser exceeded 1.5 kW of average optical power and operated at gigawatt-class peak power, with fundamental mode beam quality at a near-infrared wavelength of 1 μm. The collaborators said the system is ideal for direct laser interference patterning. Courtesy of TRUMPF.

The laser showcased in the current work was presented by Ph.D. student Johanna Dominik at the Advanced Solid State Lasers Conference this year. The system builds on TRUMPF’s commercially available TruMicro series 6000 based on InnoSlab technology as a front end. In Dominik’s demonstration, the system operated at an average power of 300 W, followed by thin-disk laser booster stage providing more than fivefold amplification.

The compact and efficient thin-disk multipass amplifier module is a technological breakthrough in terms of robustness. The disk’s large area allows extreme peak power to be generated without the need for temporal post-compression of the pulses, which are adjustable in duration between 3 and 10 ps via the front-end. A narrow spectral bandwidth below 1 nm that is ideal for direct laser interference patterning. The linear amplifier chain enables high flexibility, including burst functionality as well as the full 1.5-kW average power over a wide range of repetition rates between 375 kHz and 5 MHz, compatible with fast scanners.

Presentation of the laser system follows earlier LAMpAS project developments, including of a prototype in-line monitoring system for laser surface structuring, produced by a team at the Technische Universität (Germany) in October. That system allows monitoring of the process stability involved in laser structuring for the design of a new range of functionalized surfaces, such as easy-to-clean finishes for home appliances.