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Resistencia local negativa causada por el reflujo de electrones viscosos en el grafeno
D A Bandurin1, I Torre2, R Krishna Kumar3
1School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK.
Science (New York, N.Y.)
|February 26, 2016
Resumen
Los científicos observaron que los electrones se comportaban como un líquido viscoso en el grafeno, formando remolinos y exhibiendo fenómenos hidrodinámicos. Este descubrimiento abre nuevas vías para el estudio de la hidrodinámica electrónica en materiales avanzados.
Área de la Ciencia:
- Física de la materia condensada
- Ciencias de los materiales
- La electrónica cuántica
Sus antecedentes:
- El grafeno posee un sistema electrónico único con dispersión débil de electrones-fonones y frecuentes colisiones de electrones-electrones.
- Por encima de la temperatura del nitrógeno líquido, los electrones del grafeno pueden alcanzar el equilibrio local, comportándose como un líquido viscoso y exhibiendo fenómenos hidrodinámicos.
Objetivo del estudio:
- Proporcionar pruebas sólidas del régimen de transporte hidrodinámico de electrones en el grafeno dopado.
- Para investigar las propiedades viscosas del líquido de electrones en el grafeno.
Principales métodos:
- Observación experimental de caídas de tensión anómalas en grafeno dopado cerca de contactos de inyección de corriente.
- Análisis de patrones de flujo de electrones, específicamente la formación de remolinos de tamaño submicrómetro.
Principales resultados:
- Se detectó una caída de voltaje anómala (negativa), lo que indica la formación de remolinos de electrones.
- La viscosidad del líquido de electrones del grafeno se midió en aproximadamente 0,1 m2/s, significativamente más alta que la miel.
- Los resultados se alinean con las predicciones de la teoría de muchos cuerpos.
Conclusiones:
- El estudio proporciona pruebas convincentes de la hidrodinámica de electrones en el grafeno.
- El líquido de electrones del grafeno exhibe una viscosidad medible, ofreciendo una plataforma para estudiar estos fenómenos.
- Esta investigación demuestra el potencial para explorar la hidrodinámica de electrones en muestras de grafeno de alta calidad.
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