Fast causal information transmission in a medium with a slow group velocity.


Journal Article

It is widely believed that the velocity of information upsiloni encoded on an optical pulse is equal to the group velocity upsilong, at least when upsilong is less than the speed of light in vacuum c. On the other hand, several authors suggest that upsiloni=c, although the size of the signal traveling at this velocity may be small, thereby making it difficult to measure. Here, we measure upsiloni for pulses propagating through a resonant "slow-light" medium where upsilong approximately 0.006c. We find upsiloni=1.03c(+0.49c)-0.25c, or that upsiloni approximately 168upsilong, clearly demonstrating that the speed of information cannot be generally described by upsilong, but is characterized by its own velocity.

Full Text

Cited Authors

  • Stenner, MD; Gauthier, DJ; Neifeld, MA

Published Date

  • February 9, 2005

Published In

Volume / Issue

  • 94 / 5

Start / End Page

  • 053902 -

PubMed ID

  • 15783642

Pubmed Central ID

  • 15783642

Electronic International Standard Serial Number (EISSN)

  • 1079-7114

International Standard Serial Number (ISSN)

  • 0031-9007

Digital Object Identifier (DOI)

  • 10.1103/physrevlett.94.053902


  • eng