Signal Velocity, Causality, and Quantum Noise in Superluminal Light Pulse Propagation
A. Kuzmich, Arthur Dogariu, L. J. Wang +2 more
We consider pulse propagation in a linear anomalously dispersive medium where the group velocity exceeds the speed of light in vacuum ( c) or even becomes negative. A signal velocity is defined operationally based on the optical signal-to-noise ratio, and is computed for cases appropriate to the recent experiment where such a negative group velocity was observed. It is found that quantum fluctuations limit the signal velocity to values less than c.
arXiv:physics/0101068•Physical Review Letters•Apr 30, 2001•198 citations