Share Email Print

Proceedings Paper

Thermal excitation of d band electrons in Au: implications for laser-induced phase transformations
Author(s): Zhibin Lin; Leonid V. Zhigilei
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

The temperature dependences of the electron heat capacity and the electron-phonon coupling factor are investigated for Au based on the electron density of states obtained from ab initio electronic structure calculations. Thermal excitation of d band electrons leads to a significant (up to an order of magnitude) increase in the electronphonon coupling factor and makes a considerable contribution to the electron heat capacity in the range of electron temperatures typically realized in femtosecond laser material processing applications. Simulations performed with a combined atomistic-continuum method demonstrate that the increase in the strength of the electron-phonon coupling at high electron temperatures leads to a faster lattice heating, generation of stronger thermoelastic stresses, and a significant decrease in the time of the onset of the melting process. The timescale of the melting process predicted in the simulation accounting for the thermal excitation of d band electrons is in excellent agreement with the results of recent time-resolved electron diffraction experiments. A simulation performed with commonly used approximations of a constant electron-phonon coupling factor and a linear temperature dependence of the electron heat capacity, on the other hand, significantly overpredicts the time of the beginning of the melting process, supporting the importance of the electron density of states effects and thermal excitation of lower band electrons for realistic modeling of femtosecond pulse laser processing.

Paper Details

Date Published: 7 June 2006
PDF: 14 pages
Proc. SPIE 6261, High-Power Laser Ablation VI, 62610U (7 June 2006); doi: 10.1117/12.674636
Show Author Affiliations
Zhibin Lin, Univ. of Virginia (United States)
Leonid V. Zhigilei, Univ. of Virginia (United States)

Published in SPIE Proceedings Vol. 6261:
High-Power Laser Ablation VI
Claude R. Phipps, Editor(s)

© SPIE. Terms of Use
Back to Top