dorsal/arxiv
View SchemaTransparent Anomalous Dispersion and Superluminal Light Pulse Propagation at a Negative Group Velocity
| Authors | A. Dogariu, A. Kuzmich, L. J. Wang |
|---|---|
| Categories | |
| ArXiv ID | physics/0012060 |
| URL | https://arxiv.org/abs/physics/0012060 |
| DOI | 10.1103/PhysRevA.63.053806 |
Abstract
Anomalous dispersion cannot occur in a transparent passive medium where electromagnetic radiation is being absorbed at all frequencies, as pointed out by Landau and Lifshitz. Here we show, both theoretically and experimentally, that transparent linear anomalous dispersion can occur when a gain doublet is present. Therefore, a superluminal light pulse propagation can be observed even at a negative group velocity through a transparent medium with almost no pulse distortion. Consequently, a {\it negative transit time} is experimentally observed resulting in the peak of the incident light pulse to exit the medium even before entering it. This counterintuitive effect is a direct result of the {\it rephasing} process owing to the wave nature of light and is not at odds with either causality or Einstein's theory of special relativity.
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"abstract": "Anomalous dispersion cannot occur in a transparent passive medium where\nelectromagnetic radiation is being absorbed at all frequencies, as pointed out\nby Landau and Lifshitz. Here we show, both theoretically and experimentally,\nthat transparent linear anomalous dispersion can occur when a gain doublet is\npresent. Therefore, a superluminal light pulse propagation can be observed even\nat a negative group velocity through a transparent medium with almost no pulse\ndistortion. Consequently, a {\\it negative transit time} is experimentally\nobserved resulting in the peak of the incident light pulse to exit the medium\neven before entering it. This counterintuitive effect is a direct result of the\n{\\it rephasing} process owing to the wave nature of light and is not at odds\nwith either causality or Einstein\u0027s theory of special relativity.",
"arxiv_id": "physics/0012060",
"authors": [
"A. Dogariu",
"A. Kuzmich",
"L. J. Wang"
],
"categories": [
"physics.optics",
"physics.gen-ph"
],
"doi": "10.1103/PhysRevA.63.053806",
"title": "Transparent Anomalous Dispersion and Superluminal Light Pulse Propagation at a Negative Group Velocity",
"url": "https://arxiv.org/abs/physics/0012060"
},
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