Growth of a Wave-group when the Group-velocity is Negative
نویسندگان
چکیده
منابع مشابه
Negative Group Velocity
In more detail, consider a classical model of matter in which spectral lines are associated with oscillators. In particular, consider a gas of atoms with two closely spaced spectral lines of angular frequencies ω1,2 = ω0 ± Δ/2, where Δ ω0. Each line has the same damping constant (and spectral width) γ. Ordinarily, the gas would exhibit strong absorption of light in the vicinity of the spectral ...
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The dynamics of wave propagation in media with negative index of refraction is analyzed through analytical calculations, simulations, and experiments. Using a free space setup, the transmission characteristics of two split ring resonator and strip wire left-handed media (LHM), designed for operation at K -band frequencies (18-26 GHz), are measured. The first LHM, which is 3 unit cells long in t...
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In Physics, causality is a fundamental postulation arising from the second law of thermodynamics. It states that, the cause of an event precedes its effect. In the context of Electromagnetics, the relativistic causality limits the upper bound of the velocity of information, which is carried by electromagnetic wave packets, to the speed of light in free space (c). In anomalously dispersive media...
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Scientific community has well recognized that a Lorentzian medium exhibits anomalous dispersion behavior in its resonance absorption region. To satisfy the Krammers-Kronig relation, such an anomalous region has to be accompanied with significant loss, and thus, experimental observations of negative group velocity in this region generally require a gain-assisted approach. In this letter, we demo...
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ژورنال
عنوان ژورنال: Nature
سال: 1905
ISSN: 0028-0836,1476-4687
DOI: 10.1038/071607b0