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Ir superconductividad inducida por dopaje en el sistema SmFeAsO
Yong Liang Chen1, Cui Hua Cheng, Ya Jing Cui
1Key Laboratory of Advanced Technology of Materials (Ministry of Education of China), Superconductivity R&D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu, Sichuan 610031, China.
Journal of the American Chemical Society
|July 15, 2009
Resumen
El dopaje de iridio (Ir) en SmFeAsO induce la superconductividad a 16 K. Este dopaje de metales de transición 5d altera el ángulo de enlace As-Fe-As de manera diferente al dopaje de la capa de reserva de carga.
Área de la Ciencia:
- Física del estado sólido Física del estado sólido
- Ciencia de los materiales Ciencia de los materiales.
- La superconductividad es la superconductividad.
Sus antecedentes:
- El óxido de arseniuro de hierro de samario (SmFeAsO) es un compuesto progenitor de la familia de superconductores a base de hierro.
- Comprender los efectos del dopaje es crucial para afinar las propiedades superconductoras.
Objetivo del estudio:
- Para investigar el efecto del dopaje del metal de transición 5d Iridio (Ir) en SmFeAsO.
- Explorar la inducción de la superconductividad y su correlación con los cambios estructurales.
Principales métodos:
- El dopaje químico de iridio (Ir) en la red SmFeAsO en aproximadamente 15 atomo %.
- Análisis estructural para determinar cambios en los ángulos de enlace, específicamente el ángulo de enlace As-Fe-As (beta).
Principales resultados:
- Inducción exitosa de la superconductividad con una temperatura crítica (Tc) de 16 K.
- Se observó una disminución en el ángulo de enlace As-Fe-As (beta) debido al dopaje de Ir.
- Se demostró que el efecto del dopaje de IR en la beta difiere del dopaje en las capas de reserva de carga.
Conclusiones:
- El dopaje de metales de transición 5d con iridio es una estrategia efectiva para inducir la superconductividad en SmFeAsO.
- La modificación estructural observada (disminución de beta) es un factor clave en la superconductividad inducida.
- El sitio de dopaje influye significativamente en la respuesta estructural y las propiedades superconductoras.
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