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Radicales de espín polarizados con un tiempo de relajación de la red de espín extremadamente largo a temperatura
Kana Orihashi1, Akio Yamauchi1, Saiya Fujiwara2
1Department of Applied Chemistry, Graduate School of Engineering and Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
Journal of the American Chemical Society
|December 11, 2023
Resumen
Los investigadores crearon radicales polarizados de espín de larga duración a temperatura ambiente dentro de un marco metálico-orgánico. Este avance permite avances potenciales en las aplicaciones de detección cuántica y polarización nuclear dinámica.
Área de la Ciencia:
- Ciencias de los materiales
- Ciencia de la información cuántica
- Física Química
Sus antecedentes:
- La generación de la polarización de espín es crucial para la ciencia de la información cuántica y la polarización nuclear dinámica.
- Lograr espines de electrones polarizados con largos tiempos de relajación de la rejilla de espín (T1) a temperatura ambiente ha sido un desafío significativo.
Objetivo del estudio:
- Para realizar radicales de espín polarizado con T1 excepcionalmente largo a temperatura ambiente.
- Investigar el potencial de las estructuras metal-orgánicas (MOF) para albergar y controlar la polarización de espín.
Principales métodos:
- Integración de cromóforos de azaceno dentro de un marco metálico-orgánico (MOF).
- Generación de radicales persistentes mediante fotoexcitación y separación de cargas.
- Transferencia de la polarización de espín de los tripletes fotoexcitados a los radicales persistentes.
- Mediciones de resonancia de espín de electrones de pulso (ESR) para determinar los tiempos de relajación.
Principales resultados:
- Se generaron con éxito radicales polarizados por espín con tiempos de relajación de la red de espín extremadamente largos (T1) de 214 μs a temperatura ambiente.
- Se observaron tiempos de relajación de espín-espín relativamente largos (T2) de hasta 0,98 μs para los radicales.
- Se ha demostrado la transferencia de la polarización de espín de los estados de fotoexcitación a los radicales persistentes dentro del MOF.
Conclusiones:
- Se logró una polarización de espín largo sin precedentes en MOF a temperatura ambiente, superando las limitaciones anteriores.
- El sistema MOF desarrollado, con nanoporos accesibles, es una plataforma prometedora para la futura detección cuántica y la polarización nuclear dinámica.
- Este trabajo sienta las bases para aplicaciones avanzadas que requieren una polarización de espín estable y de larga duración.
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