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Transporte térmico cuantizado en uniones de un solo átomo

Longji Cui¹, Wonho Jeong¹, Sunghoon Hur¹

¹Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.

Science (New York, N.Y.)

|February 18, 2017

Resumen

Los investigadores midieron la conductividad térmica de las uniones de un solo átomo en los cables de oro y platino. Descubrieron que la conductividad térmica se cuantifica a temperatura ambiente, lo que confirma los principios de transporte térmico cuántico.

Área de la Ciencia:

Física de la materia condensada
La mecánica cuántica
Nanotecnología

Sus antecedentes:

Comprender el transporte térmico a escala atómica es crucial para explorar los fenómenos cuánticos.
Los estudios anteriores carecían de la resolución para sondear la conductividad térmica en contactos atómicos individuales.

Objetivo del estudio:

Para medir experimentalmente la conductividad térmica de las uniones de un solo átomo en alambres metálicos.
Investigar los efectos cuánticos en el transporte térmico a escala atómica.
Para validar la ley de Wiedemann-Franz en el contacto atómico.

Principales métodos:

Utilizó nuevas sondas de escaneo calorimétrico de resolución picowatt para mediciones precisas.
Equipo fabricado a medida para lograr una resolución de unión de un solo átomo.
Conductancia térmica medida en las uniones atómicas de oro y platino.

Principales resultados:

Conductancia térmica cuantizada demostrada en uniones de un solo átomo de oro a temperatura ambiente.
Confirmó la validez de la ley de Wiedemann-Franz incluso en el nivel de contacto de un solo átomo.
Descubrimientos experimentales explicados cuantitativamente utilizando el marco de Landauer para el transporte térmico cuántico.

Conclusiones:

Las técnicas experimentales permiten estudios detallados del transporte térmico cuántico en sistemas atómicos y moleculares.
Los hallazgos proporcionan una base para investigar cuestiones fundamentales, anteriormente inaccesibles en el transporte térmico a nanoescala.
El estudio abre nuevas vías para explorar los efectos cuánticos en los materiales a nivel atómico.

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