Negative group velocity and group delay in left-handed media

The dynamics of wave propagation in media with negative index of refraction is analyzed through analytical calculations, simulations, and experiments. Using a free space setup, the transmission characteristics of two split ring resonator and strip wire left-handed media (LHM), designed for operation at K-band frequencies (18-26 GHz), are measured. The first LHM, which is 3 unit cells long in the propagation direction, exhibits a maximum negative group delay of -0.9 ns. The, second LHM (4 unit cells long) exhibits a maximum negative group delay of -1.2 ns. For both LHM the bandwidth of the negative group delay (and hence the negative group velocity), region was approximately 250 MHz.