Skip to main content

Pushing ultrafast laser material processing into a new regime of plasma-controlled ablation

Periodic Reporting for period 4 - PULSAR (Pushing ultrafast laser material processing into a new regime of plasma-controlled ablation)

Reporting period: 2021-01-01 to 2021-12-31

Ultra-intense femtosecond laser pulses promise to become a fast, universal, predictable and green tool for material processing at micro and nanometric scale. The recent tremendous increase in commercially available femtosecond laser energy at high repetition rate opens a wealth of novel perspectives for mass production. But even at high energy, laser processing remains limited to high-speed scanning point by point removal of ultra-thin nanometric layers from the material surface. This is because the uncontrolled laser-generated free-electron plasma shields against light and prevents reaching extreme internal temperatures at very precise nanometric scale.
PULSAR aimed at breaking this barrier and developing a radically different concept of laser material modification regime based on free-electron plasma control.
PULSAR has developed a combination of new simulations of laser-plasma interaction, including the development of a code and experimental tools to characterize laser-induced plasma densities. PULSAR key concept is highly generic and the results have initiated new research across laser and plasma material processing, plasma physics and ultrafast optics.
PULSAR has developed a complete theoretical, numerical and experimental platform to characterize, understand and control nanometric plasmas generated in the bulk of transparent materials. The energy deposition process is crucial to understand the structuration of matter that follows after the laser pulse went through the medium. PULSAR team has built two complementary numerical codes to describe laser matter interaction when an ultrashort, femtosecond, pulse propagates inside a transparent medium such as glass and generates a plasma. In parallel, a novel experimental approach for plasma characterization has been built.
The fundamental insights offered by simulations and characterization tools have enabled the development of new means to confine laser-matter interaction, to successfully increase ablation efficiency in various geometries. Our results have been reported, to date, in 16 journal publications, 2 book chapters, 31 invited presentations, 34 contributions to international conferences.
The platform PULSAR has built is uniquely positioned to explore laser-matter interaction. This has enabled the understanding of several long-standing problems in the field of ultrafast laser materials processing. This is highly enabling to design novel strategies to process materials at high-speed, high efficiency and extreme spatial resolution.
ultra-thick glass cutting via ultrafast stealth dicing with shaped beams
Laser beams in our experimental setup