Abstract: Pattern formation phenomena are observed in different non-linear systems, such as chemical reactions, liquid and soft matter, granular media and plasmas. On the other hand, formation of periodic patterns is also common in linear optics, e. g., they are observed in diffraction or interference experiments. Recently periodic and quasi-periodic structures have been reported on metallic surfaces modified by femtosecond laser ablation. Periodic stripes, also known as LIPSS (Laser Induced Periodic Surface Structures) appear in the melt layers of metals, semiconductors and dielectrics after the exposure to single or multiple laser pulses. Although the pattern is known since 50 years, it is still not clear whether this an example of optical or pattern-formation phenomena. The talk is focused on possible physical mechanisms of the LIPSS formation. Assignment of the observed periodic and quasi-periodic structures to surface plasmons or to hydrodynamic instabilities in superheated melt are analysed. Ideas for control and applications of the patterns are discussed.
Information on participating / attending:
Interessierte sind herzlich eingeladen!
Kaffee ab 16:30 Uhr vor dem GSR.
Organisation: Prof. H. Fehske und Prof. Dr. L. Schweikhard
Institut für Physik, Felix-Hausdorff-Straße 6, 17489 Greifswald
Telefon 03834 86-4700, http://www.physik.uni-greifswald.de
Date:
05/15/2014 17:00 - 05/15/2014 18:00
Event venue:
Institut für Physik
Hörsaal
Felix-Hausdorff-Straße 6
17489 Greifswald
Mecklenburg-Vorpommern
Germany
Target group:
Scientists and scholars, Students
Relevance:
regional
Subject areas:
Physics / astronomy
Types of events:
Presentation / colloquium / lecture
Entry:
02/20/2014
Sender/author:
Sabine Köditz
Department:
Presse- und Informationsstelle
Event is free:
no
Language of the text:
German
URL of this event: http://idw-online.de/en/event46454
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