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Single-Molecule Imaging of Nuclear Transport
Published on: June 9, 2010
Acoplamiento nuclear y polarización en las uniones de transporte molecular: más allá del túnel para funcionar
Michael Galperin1, Mark A Ratner, Abraham Nitzan
1Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.
Science (New York, N.Y.)
|February 23, 2008
Resumen
Las uniones moleculares exhiben respuestas no lineales de tensión-corriente debido a los efectos de polarización. Estos fenómenos, incluidos el bloqueo de Coulomb y la conmutación, son impulsados por la carga y la polarización electrónica / vibratoria.
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:
- Se investigan las uniones moleculares para aplicaciones de dispositivos, con respuestas no lineales a voltajes finitos.
- La polarización molecular influye significativamente en el transporte de carga, lo que lleva a complejas características de corriente-voltaje.
Objetivo del estudio:
- Presentar un marco unificado para la comprensión de los fenómenos de transporte no lineal en las uniones moleculares.
- Para dilucidar las funciones de carga, correlación y polarización en dispositivos electrónicos moleculares.
Principales métodos:
- Análisis de la investigación experimental sobre el transporte de cargas en las uniones moleculares.
- Consideraciones teóricas de las interacciones electrón-vibración y la polarización electrónica/vibracional.
Principales resultados:
- A bajas tensiones, el acoplamiento débil de electrones-vibraciones permite la espectroscopia de túnel de electrones inelástica.
- A tensiones más altas, el acoplamiento fuerte conduce al bloqueo de Coulomb, resistencia diferencial negativa, conmutación, histeresis, calentamiento y reacciones químicas.
Conclusiones:
- El transporte no lineal en las uniones moleculares se rige por una interacción general de efectos de carga, correlación y polarización.
- Estos efectos son cruciales para el desarrollo de dispositivos electrónicos moleculares con respuestas sintonizables.
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