Ablation phenomena by intense terahertz vortex beam

• Published in: Applied physics. A, Materials science & processing Vol. 128; no. 9
• Main Authors: Wang, You Wei, Segawa, Sadashi, Shimizu, Tomoki, Agulto, Verdad C., Mag-usara, Valynn Katrine, Kato, Kosaku, Miyamoto, Katsuhiko, Omatsu, Takashige, Makino, Kotaro, Tominaga, Junji, Isoyama, Goro, Asakawa, Makoto, Nakajima, Makoto
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-09-2022; Springer Nature B.V
• Subjects: Applied physics; Characterization and Evaluation of Materials; COLA 2021/2022; Condensed Matter Physics; Electron beams; Free electron lasers; Laser ablation; Machines; Manufacturing; Materials science; Nanotechnology; Optical and Electronic Materials; Phase change materials; Phase plates; Physics; Physics and Astronomy; Processes; S.i. : Cola 2021/2022; Surfaces and Interfaces; Thin Films; Vortex beam; LIPSS; Free electron laser; Terahertz wave; Ablation
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-022-05970-7

We have successfully generated a highly efficient terahertz (THz) vortex beam using a THz free-electron laser incident to a spiral phase plate (SPP). The singularity at the center is apparently observed in the image of the transmitted beam after the SPP. We demonstrate the THz vortex beam-induced laser ablation on phase change materials, Ge
2
Sb
2
Te
5
and GeTe/Sb
2
Te
3
. The ablation marks show an annular spatial form and modulated laser-induced periodic surface structures (LIPSS) pattern. These observations can be attributed to the torque of the THz vortex.