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Refrigeración por cavidad de una micro palanca
Constanze Höhberger Metzger1, Khaled Karrai
1Center for NanoScience and Sektion Physik, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 München, Germany.
Nature
|December 24, 2004
Resumen
Los investigadores demuestran el enfriamiento óptico pasivo de un resonador micro-mecánico, reduciendo sus vibraciones térmicas. Este avance en las técnicas de enfriamiento láser podría avanzar en los experimentos macroscópicos de superposición cuántica.
Área de la Ciencia:
- La física cuántica es la física cuántica.
- La óptica es la óptica.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- La realización de estados cuánticos entrelazados entre objetos macroscópicos y fotones es un objetivo clave en la física cuántica.
- Los esquemas actuales de enfriamiento láser a menudo requieren una retroalimentación activa para amortiguar el movimiento térmico, similar al enfriamiento pasivo de átomos.
Objetivo del estudio:
- Proporcionar evidencia experimental directa para el enfriamiento óptico pasivo (intrínseco) de un resonador micromecánico.
- Explorar nuevos esquemas de enfriamiento láser para estados cuánticos macroscópicos.
Principales métodos:
- Utilizó la presión fototérmica inducida por la cavidad para controlar activamente un resonador micro-mecánico.
- Centrado en apagar las fluctuaciones vibratorias brownianas de un microlevador de silicio recubierto de oro.
Principales resultados:
- Se logró un enfriamiento óptico pasivo de la micro palanca desde la temperatura ambiente a una temperatura efectiva de 18 K.
- Demostró la supresión del movimiento térmico browniano a través del amortiguamiento óptico intrínseco.
Conclusiones:
- El enfriamiento óptico pasivo de los resonadores micromecánicos es factible experimentalmente.
- La extensión de este método podría conducir a alcanzar el límite cuántico para los estados macroscópicos de superposición cuántica.
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