Signal velocity and group velocity for an optical pulse propagating through a GaAs cavity

Author/Creator ORCID

Date

2003-07-11

Department

Program

Citation of Original Publication

Marco Centini et al., Signal velocity and group velocity for an optical pulse propagating through a GaAs cavity, Phys. Rev. E Vol. 68, Iss. 1 (2003), https://doi.org/10.1103/PhysRevE.68.016602

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Public Domain Mark 1.0
This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.

Subjects

Abstract

We present measurements of the signal and group velocities for chirped optical pulses propagating through a GaAs cavity. The signal velocity is based on a specified signal-to-noise ratio at the detector. Under our experimental conditions, the chirp substantially modifies the group velocity of the pulse, but leaves the signal velocity unaltered. At unity transmittance, the velocities are equal. In general, when the transmittance is less than unity, the group velocity is faster than the signal velocity. While the group velocity can be negative, the signal velocity is always less than c/n, where c is the speed of light in vacuum and n is the refractive index of GaAs. To our knowledge, this is the first measurement of both the group velocity and the signal velocity in any system.