English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

We present a theoretical study of the ultrafast electron dynamics intransition metals using ultrashort pulsed laser beams. The significantinfluence of the contribution of the dynamics of produced nonthermal electronsto electron thermalisation and electron-phonon interaction is thoroughlyinvestigated within a range of values of the pulse duration (i.e. from 10fs to2.3ps). The theoretical model elaborates firstly on possible transient changesof optical parameters during irradiation due to the presence of thenon-equilibrium electrons and the modification of the electron distributionfunction in a material characterized by a variable electron density of statesaround the Fermi energy. The model correlates the role of nonthermal electrons,relaxation processes and induced stress-strain fields. Simulations arepresented by choosing Nickel (Ni) as a test material to compute electron-phononrelaxation time due to its large electron-phonon coupling constant that expectsto reveal more conclusively the influence of the non-equilibrium electrons. Wedemonstrate the consideration of the above factors leads to significant changescompared to the results the traditional Two Temperature Model (TTM) provides.The proposed model predicts a substantially (~33%) smaller damage threshold anda large increase of the stress (~20%, at early times) which firstly underlinesthe role of the nonthermal electron interactions and secondly enhances itsimportance with respect to the precise determination of laser specifications inmaterial micromachining techniques.

Ultrafast dynamics of non-equilibrium electrons and strain generation under femtosecond laser irradiation of Nickel