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La supresión de los desplazamientos de colisión en un reloj de celosía que interactúa fuertemente
Matthew D Swallows1, Michael Bishof, Yige Lin
1JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA.
Science (New York, N.Y.)
|February 5, 2011
Resumen
Los investigadores redujeron los cambios de frecuencia en los relojes de celosía de estroncio mediante el uso de interacciones atómicas fuertes. Este avance mejora tanto la precisión como la exactitud de los relojes atómicos de muchos átomos, allanando el camino para futuras mejoras.
Área de la Ciencia:
- Física atómica es la física atómica.
- La metrología cuántica.
- Reloj Atómico Óptico Reloj Atómico Óptico
Sus antecedentes:
- Los relojes ópticos de celosía ofrecen estabilidad de alta frecuencia a través de la interrogación simultánea de muchos átomos.
- Las interacciones atómicas pueden introducir inexactitudes sistemáticas, particularmente cambios de frecuencia dependientes de la densidad, incluso en los relojes atómicos fermiónicos.
- Los desplazamientos de colisión plantean un desafío para lograr una alta precisión y exactitud en sistemas de muchos átomos.
Objetivo del estudio:
- Investigar métodos para suprimir los desplazamientos de frecuencia dependientes de la densidad en relojes ópticos de celosía.
- Para demostrar la efectividad de las interacciones atómicas fuertes en la mitigación de los desplazamientos de colisión.
- Para mejorar la precisión de los relojes de celosía de estroncio de muchos átomos.
Principales métodos:
- Utilizó un sistema de reloj de celosía de estroncio.
- Empleó fuertes interacciones atómicas para suprimir los cambios de frecuencia de colisión.
- Interrogó a un gran conjunto de átomos fermiónicos simultáneamente.
Principales resultados:
- Se redujo con éxito el desplazamiento de frecuencia de colisión en el reloj de celosía de estroncio.
- Disminuyó la incertidumbre del desplazamiento de la frecuencia de colisión al nivel 10 (-17).
- Demostró que las interacciones fuertes pueden suprimir los cambios en los sitios de la red de múltiples átomos.
Conclusiones:
- El uso de interacciones atómicas fuertes elimina efectivamente el compromiso entre la precisión y la exactitud en los relojes atómicos de muchas partículas.
- Este enfoque permite mejorar simultáneamente la precisión y la exactitud a medida que aumenta el número de átomos interrogados.
- Los hallazgos allanan el camino para relojes ópticos de celosía más precisos y precisos.
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