Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:quant-ph/0011100 · Physical Review A

Slow-light pulses in moving media

Jaromı́r Fiurášek, Ulf Leonhardt, Renaud Parentani

Published Dec 12, 2001• 17 citations
arXivHTMLPDF

Abstract

Slow light in moving media reaches a counterintuitive regime when the flow speed of the medium approaches the group velocity of light. Pulses can penetrate a region where a counterpropagating flow exceeds the group velocity. When the counterflow slows down, pulses are reflected.
DOI
10.1103/physreva.65.011802

Related papers

Slow light in moving media

Ulf Leonhardt, Paul Piwnicki

We review the theory of light propagation in moving media with extremely low group velocity. We intend to clarify the most elementary features of monochromatic slow light in a moving medium and, whenever possible, to give an instructive simplified picture.

Journal of Modern Optics•May 15, 2001•0 citations

Slow light in moving media

Ulf Leonhardt, Paul Piwnicki

We review the theory of light propagation in moving media with extremely low group velocity. We intend to clarify the most elementary features of monochromatic slow light in a moving medium and, whenever possible, to give an instructive simplified picture.

arXiv:physics/0009093•Journal of Modern Optics•May 1, 2001•16 citations

Slow and Fast Light

Joseph E. Vornehm, Robert W. Boyd

In early 1999, a news article in the prestigious journal Nature led off with the announcement, "€œAn experiment with atoms at nanokelvin temperatures has produced the remarkable observation of light pulses traveling at velocities of only 17 m/s."€ The review continued with the understatement, "Observation of light pulses propagating at a speed no faster than a swiftly moving bicycle...comes as a surprise."€ These findings (and their review) marked the beginning of the current wave of interest in the field that has come to be called "€œslow light.â€" When we refer to "the speed of light," we typically mean c, the phase velocity of light in a vacuum, or the speed of propagation of the phase fronts of monochromatic light. The phase fronts travel more slowly through a material, propagating at the speed c/n, where n is the index of refraction of the medium. However, this ordinary slowing of the phase velocity is not slow light. "€œSlow light"€ and "€œfast light"€ refer to changes in the group velocity of light in a medium. A pulse of light can be decomposed mathematically into a group of monochromatic waves at slightly different frequencies, as in Fig. 19.1. In a dispersive material, these monochromatic waves travel at different speeds. When one views the propagation of the pulse as a whole, its apparent velocity depends on the extent of the spread of individual monochromatic-wave velocities. Each monochromatic wave travels at its own phase velocity, while the pulse travels at the group velocity. Of course, the group velocity of a pulse of light is not a new concept. The field of slow and fast light has drawn on theory and developments from the work of Sommerfeld and Brillouin from 1907 to 1914, experiments with early laser amplifiers in 1966, and other work done through the end of the 20th century. (For more of the history behind slow and fast light, see Refs. 8 and 9.)

SPIE eBooks•Mar 16, 2010•2 citations

Controlling the Velocity of Light Pulses

Robert W. Boyd, Daniel J. Gauthier

It is now possible to exercise a high degree of control over the velocity at which light pulses pass through material media. This velocity, known as the group velocity, can be made to be very different from the speed of light in a vacuum c. Specifically, the group velocity of light can be made much smaller than c, greater than c, or even negative. We present a survey of methods for establishing extreme values of the group velocity, concentrating especially on methods that work in room-temperature solids. We also describe some applications of slow light.

Science•Nov 20, 2009•353 citations

Fast Light and Superluminal Images via Four-Wave Mixing

Ryan T. Glasser, Ulrich Vogl, Paul D. Lett

Manipulating the group velocity of light has resulted in many advances, including slowing light to a car’s pace, stopping light and even forcing pulses to propagate faster than the speed of light in a vacuum. While the group velocity is equal to or less than the speed of light in a vacuum (c) when propagating through a medium exhibiting normal dispersion, anomalous dispersion allows the group velocity to be greater than c, or even negative. Strangely, the peak of a pulse propagating with a negative group velocity through a medium appears to exit the medium before entering it. This is a result of interference from spectral components of a pulse propagating with different phase velocities in the medium.

Optics and Photonics News•Dec 1, 2012•0 citations

Coherent Control and Nonlinear Wave Mixing in Slow Light Media

Jacob B. Khurgin, R.S. Tucker

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253 The propagation of light in dispersive media can be described by five different kinds of wave velocities [1-3]: • Phase velocity, which is the speed at which the zero crossings of the carrier wave move • Group velocity, at which the peak of a wave packet moves • Energy velocity, at which the energy is transported by the wave • Signal velocity, at which the half-maximum wave amplitude moves • Front velocity, at which the first appearance of a discontinuity moves Generally, all five velocities can differ from each other, although in a linear passive dispersive media, they coincide and are, usually, less than the light velocity in vacuum. Recently, experimental demonstrations [4-6] in variousmedia show that the group velocity of light canbe reducedby10-100million compared with its vacuum phase velocity. The physics is based on very steep frequency dispersion in the vicinity of narrow resonance of electromagnetically induced transparency (EIT) [7-11].

CRC Press eBooks•Oct 8, 2018•0 citations
In early 1999, a news article in the prestigious journal Nature led off with the announcement, "€œAn experiment with atoms at nanokelvin temperatures has produced the remarkable observation of light pulses traveling at velocities of only 17 m/s."€ The review continued with the understatement, "Observation of light pulses propagating at a speed no faster than a swiftly moving bicycle...comes as a surprise."€ These findings (and their review) marked the beginning of the current wave of interest in the field that has come to be called "€œslow light.â€" When we refer to "the speed of light," we typically mean c, the phase velocity of light in a vacuum, or the speed of propagation of the phase fronts of monochromatic light. The phase fronts travel more slowly through a material, propagating at the speed c/n, where n is the index of refraction of the medium. However, this ordinary slowing of the phase velocity is not slow light. "€œSlow light"€ and "€œfast light"€ refer to changes in the group velocity of light in a medium. A pulse of light can be decomposed mathematically into a group of monochromatic waves at slightly different frequencies, as in Fig. 19.1. In a dispersive material, these monochromatic waves travel at different speeds. When one views the propagation of the pulse as a whole, its apparent velocity depends on the extent of the spread of individual monochromatic-wave velocities. Each monochromatic wave travels at its own phase velocity, while the pulse travels at the group velocity. Of course, the group velocity of a pulse of light is not a new concept. The field of slow and fast light has drawn on theory and developments from the work of Sommerfeld and Brillouin from 1907 to 1914, experiments with early laser amplifiers in 1966, and other work done through the end of the 20th century. (For more of the history behind slow and fast light, see Refs. 8 and 9.)
It is now possible to exercise a high degree of control over the velocity at which light pulses pass through material media. This velocity, known as the group velocity, can be made to be very different from the speed of light in a vacuum c. Specifically, the group velocity of light can be made much smaller than c, greater than c, or even negative. We present a survey of methods for establishing extreme values of the group velocity, concentrating especially on methods that work in room-temperature solids. We also describe some applications of slow light.
Manipulating the group velocity of light has resulted in many advances, including slowing light to a car’s pace, stopping light and even forcing pulses to propagate faster than the speed of light in a vacuum. While the group velocity is equal to or less than the speed of light in a vacuum (c) when propagating through a medium exhibiting normal dispersion, anomalous dispersion allows the group velocity to be greater than c, or even negative. Strangely, the peak of a pulse propagating with a negative group velocity through a medium appears to exit the medium before entering it. This is a result of interference from spectral components of a pulse propagating with different phase velocities in the medium.
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253 The propagation of light in dispersive media can be described by five different kinds of wave velocities [1-3]: • Phase velocity, which is the speed at which the zero crossings of the carrier wave move • Group velocity, at which the peak of a wave packet moves • Energy velocity, at which the energy is transported by the wave • Signal velocity, at which the half-maximum wave amplitude moves • Front velocity, at which the first appearance of a discontinuity moves Generally, all five velocities can differ from each other, although in a linear passive dispersive media, they coincide and are, usually, less than the light velocity in vacuum. Recently, experimental demonstrations [4-6] in variousmedia show that the group velocity of light canbe reducedby10-100million compared with its vacuum phase velocity. The physics is based on very steep frequency dispersion in the vicinity of narrow resonance of electromagnetically induced transparency (EIT) [7-11].