Computational modelling of second-harmonic generation by a femtosecond laser pulse of a few optical cycles

摘要

In this paper, we study the propagation of an extraordinary linearly polarized laser pulse of a few optical cycles and with a plane wavefront in the direction normal to the optical axis of a nonlinear uniaxial crystal of 3m symmetry group. We solve Maxwell's equations., describing the propagation of the laser pulse using the finite-difference time-domain method. We calculate the conversion efficiency, as a function of crystal length, pump energy and pulse duration. As an example, we apply our model to study the propagation of a femtosecond laser Pulse with tau = 10 fs at lambda = 810 nm wavelength in a LiNbO3; crystal of 25 mum thickness.