Controlling the Propagation Velocity of a Femtosecond Laser Pulse with Negative Index Metamaterials

We theoretically study the propagation of a femtosecond laser pulse in negative-index metamaterials, and show that its propagation velocity can be easily controlled at a certain wavelength range simply by changing the initial chirp. This phenomenon may be used as an extremely simple way to control the propagation velocity of a femtosecond laser pulse.