OPTICAL PULSE-PROPAGATION

We analyse in the domain t > 0, z > 0, the propagation of an optical p ulse launched at t = 0, z = 0 in an isotropic, homogeneous linear medi um. This corresponds for Maxwell's equations to a boundary-initial val ue problem that we solve by using the 2D-Laplace transform, We show th at the refractive index must satisfy a particular condition to make su re that the second order partial differential equation obtained from M axwell's equations is hyperbolic. Then, we discuss the inverse Laplace transform of the solution for a boundary-initial Dirac pulse in three different material media so that the solution for another type of bou ndary-initial pulse is given be; a simple convolution product. We cons ider in particular a harmonic pulse and a sequence of digital pulses. (C) 1998 Elsevier Science B.V.