Modelling and experiments of self-reflectivity under femtosecond   ablation conditions
  We present a numerical model which describes the propagation of a single femtosecond laser pulse in a medium of which the optical properties dynamically change within the duration of the pulse. We use a Finite Difference Time Domain (FDTD) method to solve the Maxwell's equations coupled to equations describing the changes in the material properties. We use the model to simulate the self-reflectivity of strongly focused femtosecond laser pulses on silicon and gold under laser ablation condition. We compare the simulations to experimental results and find excellent agreement. 
H. Zhang, S. A. Wolbers, D. M. Krol, J. I. Dijkhuis, and D. van Oosten
physics.optics