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No localidad gigante cerca del punto de Dirac en el grafeno
D A Abanin1, S V Morozov, L A Ponomarenko
1Manchester Centre for Mesoscience and Nanotechnology, University of Manchester, Manchester M13 9PL, UK.
Science (New York, N.Y.)
|April 16, 2011
Resumen
Observamos una respuesta no local significativa en las mediciones de transporte de grafeno, incluso a temperatura ambiente. Este efecto, vinculado a las corrientes de giro / valle, es crucial para comprender el grafeno.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Las mediciones de transporte son vitales para descubrir los fenómenos electrónicos en el grafeno.
- Las propiedades electrónicas únicas del grafeno cerca del punto de Dirac son de gran interés para la investigación.
- Comprender el transporte no local es clave para explorar nuevos comportamientos electrónicos.
Objetivo del estudio:
- Para investigar los fenómenos de transporte no locales en el grafeno utilizando la geometría de barras de Hall.
- Para caracterizar la respuesta no local cerca del punto de Dirac bajo campos magnéticos bajos.
- Para explorar la dependencia de la temperatura de este efecto no local.
Principales métodos:
- Realizó mediciones de transporte no locales en una configuración de barra de Hall.
- Utilizó sondas de tensión posicionadas lejos de la trayectoria de flujo de carga directa.
- Campos magnéticos aplicados tan bajos como 0,1 tesla y temperatura variada.
Principales resultados:
- Se observó una respuesta no local sustancial cerca del punto de Dirac.
- Esta respuesta persistió hasta la temperatura ambiente.
- La no localidad era consistente con las corrientes de sabor de largo alcance del levantamiento de degeneración de espín / valle.
Conclusiones:
- Las mediciones de transporte no local revelan fenómenos electrónicos clave en el grafeno.
- El efecto observado, impulsado por las corrientes de giro / valle, es significativo cerca del punto de neutralidad.
- Se espera que este hallazgo tenga un impacto en la comprensión del magnetotransporte en el grafeno.
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