Passive system with tunable group velocity for propagating electrical pulses from sub- to superluminal velocities

Alain Haché, Sophie Essiambre
2004 Physical Review E  
We report an observation of tunable group velocity from sub-luminal to superluminal in a completely passive system. Electric pulses are sent along a spatially periodic conducting medium containing a punctual nonlinearity, and the resulting amplitude-dependent phase shift allows us to control dispersion and the propagation velocity at the stop band frequency.
doi:10.1103/physreve.69.056602 pmid:15244958 fatcat:lo2eeidchjet3h6jgmpubnmqte