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Controlar la velocidad de los pulsos de luz
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
Science (New York, N.Y.)
|December 8, 2009
Resumen
Los científicos ahora pueden controlar la velocidad de los pulsos de luz en los materiales, logrando velocidades de grupo extremadamente lentas, rápidas o incluso negativas. Esta encuesta se centra en los métodos sólidos a temperatura ambiente y las aplicaciones de luz lenta.
Área de la Ciencia:
- Óptica y Fotónica.
- Física de la materia condensada Física de la materia condensada
Sus antecedentes:
- La propagación del pulso de luz en los materiales es típicamente cercana a la velocidad de la luz en el vacío (c).
- El control de la velocidad de grupo de la luz ofrece nuevas posibilidades en las tecnologías ópticas.
Objetivo del estudio:
- Estudiar métodos para lograr velocidades de grupo extremas de la luz en materiales.
- Centrarse en las técnicas aplicables a los sólidos a temperatura ambiente.
- Para explorar las aplicaciones de la luz lenta.
Principales métodos:
- Revisión de enfoques experimentales y teóricos para manipular la velocidad del pulso de luz.
- Investigar técnicas que permitan velocidades de grupo significativamente diferentes de c.
- Métodos de resaltado adecuados para materiales en estado sólido a temperaturas ambientales.
Principales resultados:
- Demostración de métodos para lograr velocidades de grupo mucho más pequeñas que c (luz lenta).
- Observación de velocidades de grupo mayores que c (propagación superluminal).
- Realización experimental de velocidades de grupo negativas, donde los pulsos parecen emerger antes de entrar.
Conclusiones:
- Se puede lograr un alto control sobre la velocidad del grupo de pulsos de luz en los materiales.
- Los métodos de estado sólido a temperatura ambiente ofrecen vías prácticas para velocidades de grupo extremas.
- La luz lenta y otros fenómenos de velocidad extrema tienen aplicaciones potenciales en el procesamiento de señales ópticas y líneas de retardo.
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