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Medición directa de la coherencia de tercer orden de largo alcance en condensados de Bose-Einstein
S S Hodgman1, R G Dall, A G Manning
1Australian Research Council Centre of Excellence for Quantum Atom Optics, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200, Australia.
Science (New York, N.Y.)
|February 26, 2011
Resumen
Los investigadores midieron las correlaciones atómicas, observando el agrupamiento atómico cerca de las temperaturas de la condensación de Bose-Einstein (BEC). Ellos confirmaron el BEC.
Área de la Ciencia:
- La física cuántica es la física cuántica.
- Física atómica La física atómica es la física de los átomos.
- Estudios de condensados.
Sus antecedentes:
- Comprender la coherencia de la luz se basa en las funciones de correlación de fotones.
- Las correlaciones son fundamentales tanto para la luz como para la materia.
- El condensado de Bose-Einstein (BEC) es un estado de la materia con propiedades cuánticas únicas.
Objetivo del estudio:
- Para medir las funciones de correlación de segundo y tercer orden para átomos.
- Para investigar el agrupamiento atómico y la coherencia de largo alcance en BEC.
Principales métodos:
- Medición simultánea de las funciones de correlación atómica de segundo y tercer orden.
- Observación de los tiempos de llegada de átomos térmicos cerca de la transición BEC.
Principales resultados:
- Se observó el agrupamiento atómico para pares y trillizos de átomos térmicos por encima de la temperatura BEC.
- Demostró de manera concluyente la coherencia a largo plazo de las BEC hasta el tercer orden a temperaturas más bajas.
Conclusiones:
- Los hallazgos apoyan las predicciones de coherencia de largo alcance en BECs, análogas a la luz coherente.
- Las correlaciones atómicas proporcionan información sobre los estados cuánticos de la materia.
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