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Extraordinaria conducción térmica mediada por polaritones de fonones en no equilibrio
Zhiliang Pan1, Guanyu Lu1, Xun Li2
1Department of Mechanical Engineering, Vanderbilt University, Nashville, TN, USA.
Nature
|October 25, 2023
Resumen
Los polaritones de fonones de superficie (SPhP) aumentan significativamente la conducción de calor en los nanocables 3C-SiC. Este descubrimiento permite el control del transporte de energía y podría mejorar el diseño de dispositivos de estado sólido.
Área de la Ciencia:
- Física de la materia condensada
- Ciencias de los materiales
- Nanotecnología
Sus antecedentes:
- Las ondas superficiales pueden inducir fenómenos de transporte únicos.
- Los polaritones de fonones de superficie (SPhPs) surgen de la luz infrarroja y el acoplamiento de fonones ópticos, que potencialmente ayudan a la conducción de calor en los materiales polares.
- Las pruebas experimentales anteriores sobre las contribuciones del SPhP al transporte de calor han sido limitadas.
Objetivo del estudio:
- Investigar experimentalmente la contribución de los SPhP al transporte térmico en los nanocables 3C-SiC.
- Cuantificar el aumento de la conductividad térmica debido a los SPhP.
- Explorar métodos para el lanzamiento y el control de SPhP para mejorar el transporte térmico.
Principales métodos:
- Mediciones sistemáticas del transporte térmico en nanocables 3C-SiC con y sin recubrimiento de oro.
- Utilizando recubrimientos de oro para lanzar SPhPs.
- Analizar la conductividad térmica basada en la longitud de los nanocables y las dimensiones del recubrimiento de oro.
Principales resultados:
- Los SPhP excitados térmicamente mejoran sustancialmente la conductividad térmica de las porciones de nanocables de SiC sin recubrimiento.
- Se encontró que la conductividad térmica de SPhP antes de la descomposición era más de dos órdenes de magnitud mayor que la predicha por los modelos de equilibrio.
- La conductividad térmica mediada por SPhP mostró una proporción directa a la longitud del recubrimiento dorado.
Conclusiones:
- El lanzamiento eficiente de SPhP no equilibrados desde regiones cubiertas de oro mejora significativamente el transporte térmico.
- Los SPhP ofrecen una vía para modular el transporte de energía en sólidos y contrarrestar los efectos de tamaño clásicos.
- Esta investigación allana el camino para mejorar el diseño de dispositivos de estado sólido a través de la manipulación de SPhP.
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