Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (12): 3143-3149.doi: 10.3866/PKU.WHXB20101224

• THERMODYNAMICS,THERMOCHEMISTRY AND SOLUTION CHEMISTRY • Previous Articles     Next Articles

Molecular Dynamics Simulation of the Laser-Induced Melting of an Al Nanofilm

BAI Ming-Ze1, CHENG Li1, TANG Hong1, DOU Yu-Sheng1,2   

  1. 1. Institue of Computational Chemistry, Chongqing University of Posts and Telecommunications, Chongqing 400065, P. R. China;
    2. Department of Physical Sciences, Nicholls State University, LA 70310, USA
  • Received:2010-07-22 Revised:2010-10-12 Published:2010-12-01
  • Contact: DOU Yu-Sheng E-mail:Yusheng.Dou@nicholls.edu
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20773618, 21073242) and Natural Science Foundation of Chongqing University of Posts and Telecommunications, China (A2008-39).

Abstract:

A coupled computational technique, which combines the one dimensional two-temperature model and molecular dynamics, was used to study the melting dynamics of a nanoscale aluminum film irradiated by a femtosecond laser pulse. The model is capable of providing an atomic-level depiction of fast microscale processes in metals and gives an adequate description of laser light absorption, energy transfer, and fast electron heat conduction in metals. The simulation revealed that the electron temperature, lattice temperature, and laser induced pressure of the Al film were significantly different from those of Ni and Au films. The Al film melts globally soon after laser radiation and this is different from the Ni film, which goes through a step melting process. In addition, the Al film shows a much faster melting process than the Ni and Au films because of strong electron-phonon coupling. The melting time of the Al film by an ultrafast laser pulse is consistent with recent experimental observations, which supports the assertion that the laser induced melting of an Al film is a thermal process.

Key words: Metal Al, Laser melting, Two-temperature model, Ultrafast dynamics, Thermal melting

MSC2000: 

  • O641