Pulse-to-pulse detection of terahertz radiation emitted from the femtosecond laser ablation process

Autor: Ryo Tamaki, Tatsuki Kasai, Gaku Asai, Daiki Hata, Hajime Kubo, Yuichi Takigawa, Jun Takeda, Ikufumi Katayama
Rok vydání: 2022
Předmět:
Zdroj: Optics Express. 30:23622
ISSN: 1094-4087
Popis: Determining the dynamics of electrons and ions emitted from a target material during laser ablation is crucial for desirable control of laser processing. However, these dynamics are still challenging to understand because of a lack of ubiquitous spectroscopic tools to observe tangled-up dynamics appearing at ultrafast timescales. Here by harnessing highly sensitive single-shot terahertz time-domain spectroscopy using an echelon mirror, we investigate pulse-to-pulse temporal profile of terahertz radiation generated from the material surface. We clearly found that the carrier–envelope phase and the electric field amplitude of the terahertz waveform systematically vary between the pre- and post-ablation depending on the laser fluence and irradiated pulse numbers. Our results provide a stepping-stone towards perception of Coulomb explosion occurring throughout the laser ablation process, which is indispensable for future laser processing applications.
Databáze: OpenAIRE