The existence and properties of propagative nondispersive and nondiffracting localized envelope waves in dispersive transparent media, with either normal or anomalous group-velocity dispersion, showing subluminal group velocities and strong spatial localization are pointed out. Nonparaxial effects may lead to group-velocity reduction of several orders of magnitude. Numerical simulations are given for wave propagation in sapphire.
© 2004 Optical Society of America
Stefano Longhi, "Localized subluminal envelope pulses in dispersive media," Opt. Lett. 29, 147-149 (2004)