Superconductividad en el estado no magnético del hierro bajo presión
K Shimizu1, T Kimura, S Furomoto
1Department of Physical Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan. kshimizu@mp.es.osaka-u.ac.jp
Nature
|July 19, 2001
Resumen
El hierro se vuelve superconductor a bajas temperaturas (por debajo de 2 K) cuando se somete a altas presiones (1530 GPa). Esto ocurre en el hierro.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- El ferromagnetismo y la superconductividad son fenómenos típicamente competidores en los superconductores convencionales.
- Los metales pueden exhibir superconductividad en sus estados no magnéticos a bajas temperaturas.
- El hierro se transforma en una estructura no magnética a presiones superiores a 10 GPa, con superconductividad prevista en esta fase.
Objetivo del estudio:
- Para investigar el potencial de superconductividad en hierro no magnético bajo alta presión.
- Para confirmar experimentalmente las propiedades de superconducción predichas del hierro a presiones elevadas.
Principales métodos:
- Síntesis de alta presión y caracterización del hierro.
- Medición de la resistividad eléctrica en función de la temperatura y la presión.
- Detección del efecto Meissner para confirmar la superconductividad.
Principales resultados:
- El hierro exhibe superconductividad a temperaturas por debajo de 2 K.
- La superconductividad se observa en el hierro a presiones que oscilan entre 15 y 30 GPa.
- Una clara caída en la resistividad y el efecto Meissner confirman la transición superconductora.
Conclusiones:
- El hierro no magnético inducido a alta presión puede convertirse en superconductor.
- Estos hallazgos desafían la comprensión convencional de las fases competidoras en la superconductividad.
- El comportamiento superconductor del hierro bajo presión abre nuevas vías para la investigación de la ciencia de los materiales.
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