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Conmutación y memoria de Spin-flop en un conductor molecular.
Mitsuhiko Maesato1, Tomohito Kawashima, Yoshitomo Furushima
1Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan. maesato@kuchem.kyoto-u.ac.jp
Journal of the American Chemical Society
|October 9, 2012
Resumen
Observamos una magnetorresistencia positiva significativa y una memoria no volátil en un nuevo conductor molecular. Esto surge de la interacción entre los electrones π y los espines de los electrones d, allanando el camino para la espintrónica molecular.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
- La electrónica molecular es la electrónica molecular.
Sus antecedentes:
- Los conductores moleculares ofrecen propiedades electrónicas sintonizables.
- La interacción entre diferentes sistemas de electrones (π y d) es clave para los nuevos fenómenos.
- El ordenamiento antiferromagnético y las ondas de densidad de espín son estados electrónicos importantes.
Objetivo del estudio:
- Para investigar las propiedades de magnetotransporte de los conductores moleculares híbridos π-d.
- Explorar el origen de la magnetorresistencia observada y los efectos de memoria.
- Para demostrar el potencial de los sistemas moleculares en la espintrónica.
Principales métodos:
- Síntesis del conductor molecular híbrido π-d (DIETSe) 2FeCl4.4.
- Mediciones de transporte eléctrico bajo campos magnéticos variables.
- Análisis de los fenómenos de magnetotransporte relacionados con el ordenamiento de espín.
Principales resultados:
- Primera observación de magnetorresistencia positiva inducida por el spin-flop hasta el 100%.
- Demostración del efecto de memoria magnetorresistiva no volátil.
- Evidencia de la coexistencia de la onda de densidad de espín (SDW) y el orden antiferromagnético d-electrónico.
Conclusiones:
- Los fenómenos observados se derivan de la interacción entre la inestabilidad de los electrones π de Q1D y el antiferromagnetismo de los electrones d.
- Este descubrimiento abre nuevas vías para la espintrónica molecular y los dispositivos de memoria.
- El sistema (DIETSe) 2FeCl4 sirve como modelo para el estudio de las órdenes electrónicas y magnéticas acopladas.
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