Maybe you should read your articles before posting them.

Quote Originally Posted by second article
"Haché and Poirier emphasize that their experiment does not break any laws of physics. Although the group velocity exceeds the speed of light - an effect permitted by relativity - each component of the pulse travels slower than light. It would be impossible to transmit information faster than light because it would be encoded onto a single frequency component. "
Quote Originally Posted by first article
"Special relativity prevents any object with mass travelling at the speed of light, and the principle of causality - the notion that the cause comes before the effect - is used to rule out the possibility of superluminal (faster-than-light) travel by light itself. However, a pulse of light can have more than one speed because it is made up of light of different wavelengths. "