Wave packet propagation into a negative index medium

We examine the phenomenon of negative refraction using wave packet propagation. The behavior of a single plane wave incident from vacuum onto a flat surface of a medium with a negative index of refraction is solved analytically. The solution requires matching electromagnetic field components across the interface and produces a reflected and a refracted wave in addition to the incident wave. We form by numerical integration a (Gaussian-weighted) linear combination of these solutions. Pictures and videos that illustrate the resulting wave packet motion are presented for a variety of parameter choices. (C) 2004 American Association of Physics Teachers.