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Superconductividad a granel en el oxisulfuro de bismuto Bi4O4S3
Shiva Kumar Singh1, Anuj Kumar, Bhasker Gahtori
1Quantum Phenomena and Applications Division, National Physical Laboratory (CSIR), Dr. K. S. Krishnan Road, New Delhi 110012, India.
Journal of the American Chemical Society
|September 26, 2012
Resumen
Hemos sintetizado Bi(4)O(4)S(3) y confirmado que es un superconductor a granel con una temperatura de transición de 4.4 K. Este descubrimiento excluye la superconductividad impulsada por impurezas, abriendo nuevas vías para la investigación de sulfuros en capas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
- Química del estado sólido.
Sus antecedentes:
- Informes recientes sugieren superconductividad en sulfuros en capas.
- Bi ((4) O ((4) S ((3) es un candidato potencial para la investigación de la superconductividad.
Objetivo del estudio:
- Sintetiza Bi{4}O{4}S{3} utilizando una técnica de encapsulación al vacío.
- Caracteriza sus propiedades superconductoras.
- Investigar el origen de la superconductividad.
Principales métodos:
- Síntesis de encapsulación al vacío a 500 °C.
- Mediciones de la magnetización AC/DC.
- La magnetización isotérmica (M-H) y las mediciones de magnetotransporte.
Principales resultados:
- Sintetizado Bi(4)O(4)S(3) con una estructura tetragonal (I4/mmm).
- Se confirmó la superconductividad a granel con una temperatura de transición (T ((c)) de 4.4 K.
- Determinado campo crítico inferior (H) ~15 Oe y campo crítico superior (H) ~31 kOe.
Conclusiones:
- Bi ((4) O ((4) S ((3) exhibe superconductividad a granel, no impulsado por las impurezas.
- Los hallazgos apoyan una mayor exploración de sulfuros en capas para la superconductividad.
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