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La ingeniería de la banda de homounión isotópica a partir del diamante
H Watanabe1, C E Nebel, S Shikata
1Diamond Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 2-13, 1-1-1, Umezono, Tsukuba, Ibaraki 305-8568, Japan. hideyuki-watanabe@aist.go.jp
Science (New York, N.Y.)
|June 13, 2009
Resumen
Los investigadores crearon superredes de diamantes utilizando isótopos de carbono-12 y carbono-13 para confinar los electrones. Este nuevo enfoque demuestra el confinamiento efectivo de la portadora en el diamante, allanando el camino para nuevas aplicaciones de semiconductores.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
- La ingeniería cuántica es la ingeniería cuántica.
Sus antecedentes:
- El confinamiento del portador de carga de semiconductores se logra típicamente utilizando heterostructuras con diferentes composiciones elementales.
- Los ejemplos incluyen capas de arseniuro de galio de aluminio (AlGaAs) y arseniuro de galio (GaAs).
Objetivo del estudio:
- Para fabricar y caracterizar superredes de diamantes utilizando isótopos de carbono isotópicamente puros.
- Para demostrar el confinamiento de la portadora en el diamante a través de diferencias de brecha de banda diseñadas.
Principales métodos:
- Fabricación de estructuras de diamante multicapa utilizando isótopos de carbono-12 (12C) y carbono-13 (13C).
- Utilizando una diferencia de energía de brecha de banda de 17 milielectronvoltios para el confinamiento.
- Espectroscopia de catodoluminiscencia a 80 Kelvin para analizar la recombinación excitónica.
Principales resultados:
- Fabricación exitosa de superredes de diamantes con capas delgadas (30 nm) y gruesas (hasta 350 nm).
- Observación de la recombinación excitónica cambiando de la banda 13C de mayor energía a la banda 12C de menor energía.
- Demostración del confinamiento efectivo de electrones dentro de la estructura de la superred de diamantes.
Conclusiones:
- Las superredes de diamantes compuestas de diferentes isótopos de carbono pueden confinar efectivamente a los portadores de carga.
- Este enfoque de ingeniería isotópica ofrece un nuevo método para crear pozos cuánticos en el diamante.
- Los hallazgos abren posibilidades para dispositivos electrónicos y optoelectrónicos avanzados basados en diamantes.
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