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Perovskitas quirales bidimensionales con un gran ángulo de spin Hall y una conductividad de spin Hall colineal
Ibrahim Abdelwahab1,2, Dushyant Kumar3,4, Tieyuan Bian5
1Department of Chemistry, National University of Singapore, Singapore 117543, Singapore.
Science (New York, N.Y.)
|July 18, 2024
Resumen
Las perovskitas quirales exhiben una conversión eficiente de carga a espín, una propiedad clave para la espíntrónica. Este estudio cuantifica esta conversión, revelando el potencial para dispositivos avanzados de espín-optoelectrónica.
Área de la Ciencia:
- La tecnología Spintronics
- Ciencias de los materiales
- Química orgánica e inorgánica
Sus antecedentes:
- Las perovskitas híbridas orgánicas-inorgánicas bidimensionales son materiales spin-optoelectrónicos prometedores.
- Estos materiales poseen una textura de espín quiral.
- La eficiencia de conversión de carga a espín en estos materiales sigue siendo en gran medida no cuantificada.
Objetivo del estudio:
- Demostrar y cuantificar la conversión eléctrica de carga a espín en perovskitas quirales enantiopuras.
- Para investigar el ángulo de giro de Hall y la vida útil del giro en estos materiales.
- Para explorar la naturaleza de las corrientes de espín generadas en perovskitas quirales.
Principales métodos:
- Utilizó microscopía de escaneo fotovoltaica.
- Las perovskitas quirales enantiopuras investigadas de la fórmula (R/S-MB) 2(MA) 3Pb4I13 (n = 4).
- Se compararon los resultados con homólogos racémicos y homólogos inferiores.
Principales resultados:
- Logró una conversión de carga a espín altamente eficiente.
- Se midió un ángulo de giro Hall (θsh) del 5% y una vida útil de giro de ~ 75 picosegundos a temperatura ambiente.
- Se observaron conductividades Hall de espín convencionales y colineares, indicadas por corrientes de espín transversales y fuera de plano.
Conclusiones:
- Las perovskitas quirales enantiopuras demuestran una eficiencia de conversión de carga a espín significativa.
- Estos materiales superan a sus homólogos racémica y inferior.
- La presencia de múltiples conductividades de espín destaca su compleja dinámica de espín y el potencial para aplicaciones espintrónicas.
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