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Lectura de alta fidelidad y control de un qubit de espín nuclear en silicio
Jarryd J Pla1, Kuan Y Tan, Juan P Dehollain
1Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, New South Wales 2052, Australia.
Nature
|April 20, 2013
Resumen
Los investigadores demuestran el control eléctrico de los espines nucleares de un solo fósforo-31 en silicio, logrando una alta fidelidad para la computación cuántica. Este avance integra la lectura de espín de electrones con la manipulación de espín nuclear para el procesamiento avanzado de información cuántica.
Área de la Ciencia:
- Ciencias de la información cuántica Ciencias de la información cuántica.
- Física del estado sólido Física del estado sólido
- Microelectrónica Ingeniería de la ingeniería.
Sus antecedentes:
- La detección de espín nuclear es vital para diversas aplicaciones científicas, desde la química hasta la medicina.
- Los espines nucleares individuales, debido a su aislamiento, son prometedores para el procesamiento de información cuántica.
- Los spins nucleares de fósforo-31 (31P) en silicio ofrecen una excelente coherencia y aprovechan la industria establecida de la microelectrónica.
Objetivo del estudio:
- Para demostrar la detección eléctrica y la manipulación coherente de un solo qubit de espín nuclear 31P.
- Para lograr altas fidelidades adecuadas para la computación cuántica tolerante a fallos.
- Establecer una plataforma de control y medición eléctrica completa para la computación cuántica basada en el espín nuclear en silicio.
Principales métodos:
- Integración de la lectura de espín de electrones de un solo disparo con la resonancia de espín de electrones en el chip.
- No demolición cuántica y lectura eléctrica de un solo disparo del espín nuclear.
- Aplicación coherente de pulsos de radiofrecuencia para el funcionamiento de qubits.
Principales resultados:
- Logró una fidelidad de lectura de espín nuclear superior al 99,8%, la más alta para cualquier qubit de estado sólido.
- Demostró un tiempo de coherencia de espín nuclear de 60 milisegundos para un donante de 31P ionizado.
- Logró una fidelidad de control de puerta de un qubit superior al 98%.
Conclusiones:
- Los espines nucleares individuales de 31P en silicio se pueden controlar eléctricamente y leer con alta fidelidad.
- La tecnología de la microelectrónica de silicio se puede adaptar para el procesamiento de información cuántica basado en el espín nuclear.
- Este trabajo presenta una plataforma viable para la computación cuántica escalable y tolerante a fallos utilizando qubits de estado sólido.
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