Invited talk, co-authors: Oscar Restrepo, Charlotte Becquart, Fedwa El-Mellouhi, Othmane Bouhali, International Computational Science and Engineering Conference 2015 Doha, Qatar (11-12 May 2015)
Understanding atomistic diffusion and relaxation mechanisms remains one of the main challenges of materials science both at the experimental and numerical levels. How, indeed, can we follow the microscopic motion of atoms on time scales relevant to describe aging, crack propagation and self-assembly? For this, we need to fill the gap between thermal vibration, taking place on the picosecond time scale, and phenomena occurring overs seconds, hours and even years. With the advent of faster computers and the development of a new class of algorithms, we are now starting to bridge this time gap in complex materials, opening the door to the numerical study of crucial, but long neglected problems. In this talk, I will present the kinetic Activation-Relaxation Technique (k-ART), an off-lattice kinetic Monte Carlo algorithm with on-the-fly catalog building, a method able to follow atomistic kinetic of alloys, defective and disordered materials over more than 10 decades in time, reaching the second time scale and more. I will show recent applications to carbon diffusion in iron, relaxation of ion bombarded silicon, defect diffusion in amorphous materials and more.