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Evolución coherente libre de un sistema de espín atómico acoplado iniciado por la dispersión de electrones
Lukas M Veldman1, Laëtitia Farinacci1, Rasa Rejali1
1Department of Quantum Nanoscience, Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJ Delft, the Netherlands.
Science (New York, N.Y.)
|May 28, 2021
Resumen
Los investigadores rastrearon los giros atómicos acoplados utilizando el microscopio de túnel de barrido. Observaron que los giros se entrelazan y intercambian el momento angular solo cuando sus frecuencias de Larmor coinciden, ofreciendo información sobre la migración del estado cuántico.
Área de la Ciencia:
- Mecánica Cuántica
- Física de la materia condensada
- Ciencias de los materiales
Sus antecedentes:
- Comprender la dinámica en tiempo real de los sistemas cuánticos acoplados es crucial para controlar los estados cuánticos.
- Las excitaciones locales y su propagación son fenómenos clave en los sistemas cuánticos de muchos cuerpos.
Objetivo del estudio:
- Para investigar la evolución coherente en tiempo real de un par de giros atómicos acoplados.
- Explorar las condiciones para el entrelazamiento y el intercambio de momento angular entre giros acoplados.
- Para demostrar un nuevo método para sondear la dinámica de espín utilizando microscopía de túnel de barrido.
Principales métodos:
- Se utilizó microscopía de túnel de barrido (STM) para sondear los espines atómicos acoplados.
- Utilizó un esquema de bomba-sonda de corriente continua (CC) para la excitación de giro inducida por corriente.
- Interacción magnética apalancada entre la punta de la sonda STM y los giros atómicos para ajustar la precesión.
Principales resultados:
- Rastreó con éxito la evolución libre y coherente de los giros atómicos acoplados en tiempo real.
- Demostró que el enredo y el intercambio de momento angular ocurren solo cuando las frecuencias de Larmor coinciden.
- Proporcionó evidencia para la localización de la dispersión de espín de electrones.
Conclusiones:
- El estudio revela el papel crítico de las frecuencias de Larmor para el entrelazamiento de espín y la dinámica.
- Los hallazgos ofrecen información fundamental sobre los mecanismos de dispersión de espín de los electrones.
- Este trabajo sienta las bases para futuras investigaciones sobre la migración controlada del estado cuántico en redes de espín.
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