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Efecto Hall cuántico en una unión p-n controlada por puertas de grafeno
J R Williams1, L Dicarlo, C M Marcus
1School of Engineering and Applied Science, Harvard University, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|June 30, 2007
Resumen
Los investigadores crearon una unión p-n de grafeno utilizando un cerramiento electrostático local, lo que permite el control sobre el tipo y la densidad de la portadora. Este avance allana el camino para futuros dispositivos nanoelectrónicos bipolares basados en grafeno.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
- La nanoelectrónica es la nanoelectrónica.
Sus antecedentes:
- La estructura única de banda electrónica del grafeno facilita el control del campo eléctrico de las propiedades de la portadora.
- Esta capacidad de ajuste hace del grafeno un material prometedor para aplicaciones nanoelectrónicas bipolares.
Objetivo del estudio:
- Para realizar una unión p-n de grafeno de una sola capa con tipo de portador y densidad controlados localmente.
- Para investigar las propiedades de transporte de esta unión en el régimen cuántico de Hall.
Principales métodos:
- Fabricación de una unión p-n de grafeno de una sola capa utilizando cerraduras electrostáticas locales.
- Mediciones de transporte en el régimen cuántico de Hall.
Principales resultados:
- Se ha demostrado el cerramiento electrostático local para controlar el tipo de portador y la densidad en regiones adyacentes de grafeno.
- Se observaron nuevas mesetas de conductividad de dos terminales a 1 y 32 veces el cuántico de conductividad (e2/h) a través de la unión.
- Los resultados son consistentes con las predicciones teóricas.
Conclusiones:
- La técnica de apertura local proporciona una base para la tecnología bipolar basada en grafeno.
- Este trabajo permite nuevas investigaciones de la física de la materia condensada utilizando uniones p-n de grafeno.
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