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Control de la relajación del giro con una cavidad

A Bienfait¹, J J Pla², Y Kubo¹

¹Quantronics Group, SPEC, CEA, CNRS, Université Paris-Saclay, CEA-Saclay, 91191 Gif-sur-Yvette, France.

|February 16, 2016

Resumen

Los investigadores mejoraron la emisión espontánea de espines en sólidos utilizando una cavidad de microondas superconductora. Esto aumenta significativamente las tasas de relajación de espín, permitiendo el control bajo demanda para aplicaciones de información cuántica y resonancia magnética.

Área de la Ciencia:

La física cuántica
Física del estado sólido
La electrodinámica cuántica de la cavidad

Sus antecedentes:

La emisión espontánea es un proceso cuántico fundamental para la relajación del sistema.
La relajación del espín suele estar dominada por procesos no radiativos debido al débil acoplamiento del dipolo magnético.
El efecto Purcell demuestra una mayor emisión espontánea a través de las cavidades resonantes.

Objetivo del estudio:

Para investigar la aplicación del efecto Purcell a los espines en los sólidos.
Para lograr la emisión espontánea como el mecanismo de relajación de espín dominante.
Para permitir el control a pedido de las tasas de relajación de giro.

Principales métodos:

Acoplamiento de giros donantes en silicio a una cavidad de microondas superconductora de alta calidad.
La sintonización gira a la frecuencia de resonancia de la cavidad.
Medición de las tasas de relajación del giro.

Principales resultados:

Se logra la emisión espontánea como el mecanismo de relajación de espín dominante para espines en sólidos.
Aumento de las tasas de relajación de giro en tres órdenes de magnitud.
Control demostrado de la relajación de la energía bajo demanda.

Conclusiones:

La emisión espontánea se puede mejorar de manera controlable para los giros en sólidos.
Esta técnica ofrece un método general para la inicialización de sistemas de espín.
Los resultados allanan el camino para el acoplamiento magnético coherente de espines a fotones de microondas.

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