%0 Journal Article
%A Zaum, Ch
%A Osterloh, N
%A Darkins, R
%A Duffy, DM
%A Morgenstern, K
%D 2021
%F discovery:10164801
%I NATURE PORTFOLIO
%J Scientific Reports
%K Science & Technology, Multidisciplinary Sciences, Science & Technology - Other Topics, ABLATION, METALS, DYNAMICS, ALUMINUM, STATES, SITES, AU, AG, CU
%N 1
%T Real-space observation of surface structuring induced by ultra-fast-laser illumination far below the melting threshold
%U https://discovery.ucl.ac.uk/id/eprint/10164801/
%V 11
%X Intense short laser pulses are an intriguing tool for tailoring surface properties via ultra-fast melting of the surface layer of an irradiated target. Despite extensive studies on the interaction of femto-second laser interaction with matter, the initial steps of the morphological changes are not yet fully understood. Here, we reveal that substantial surface structure changes occur at energy densities far below the melting threshold. By using low-temperature scanning tunneling microscopy we resolve atomic-scale changes, i.e. the creation of nanosized adatom and vacancy clusters. The two cluster types have distinct non-linear fluence-dependencies. A theoretical analysis reveals their creation and motion to be non-thermal in nature. The formation of these atomistic changes, individually resolved here for the first time, recast our understanding of how surfaces respond to low-intensity ultra-short laser illumination. A visualization and control of the initial morphological changes upon laser illumination are not only of fundamental interest, but pave the way for the designing material properties through surface structuring.
%Z This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.