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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Dinámica de Gigahertz de un espín cuántico único fuertemente impulsado
G D Fuchs1, V V Dobrovitski, D M Toyli
1Center for Spintronics and Quantum Computation, University of California, Santa Barbara, CA 93106, USA.
Science (New York, N.Y.)
|December 8, 2009
Resumen
Los investigadores exploraron la dinámica de conducción fuerte en sistemas de dos niveles utilizando un centro de vacío de nitrógeno en el diamante. Observaron una rotación de espín sub-nanosegundo, revelando nuevas oportunidades de control cuántico más allá de las aproximaciones convencionales.
Área de la Ciencia:
- La física cuántica es la física cuántica.
- Sistemas de espín de estado sólido.
Sus antecedentes:
- Los sistemas de dos niveles son fundamentales en tecnologías como la RMN y los relojes atómicos.
- El control coherente típicamente utiliza campos oscilantes con escalado de velocidad lineal.
Objetivo del estudio:
- Investigue el régimen de "conducción fuerte" donde la escala lineal se rompe.
- Medir la dinámica de temperatura ambiente de un único centro de vacío de nitrógeno en el diamante.
Principales métodos:
- Utilizó un campo oscilante para impulsar la dinámica del sistema.
- Se utiliza el paso adiabático para calibrar la rotación del giro.
- Dinámica medida a nivel de un solo giro.
Principales resultados:
- Se observaron dinámicas complejas en el régimen de conducción fuerte.
- La dinámica de espín medida en escalas de tiempo subnanosegundos.
- Desglose demostrado de la aproximación de la onda giratoria.
Conclusiones:
- Las fuertes dinámicas de conducción ofrecen nuevas posibilidades para el control cuántico.
- La manipulación de espín por debajo del nanosegundo es posible.
- Desafía la comprensión convencional del control de sistemas cuánticos.
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