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Updated: Jun 18, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Controlling the velocity of light pulses
Robert W Boyd1, Daniel J Gauthier
1The Institute of Optics and Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627, USA. boyd@optics.rochester.edu
Abstract:
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.
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