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Resistividad de temperatura lineal desde una tasa de dispersión isotrópica de Planck

  • 0Département de physique, Institut quantique, RQMP, Université de Sherbrooke, Sherbrooke, Québec, Canada.
Nature +

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29 de julio de 2021

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29 de julio de 2021

Ver abstracta en PubMed

Resumen

Este resumen es generado por máquina.

Los metales extraños muestran una inusual resistencia a la temperatura lineal debido a la dispersión. Este estudio revela que esta dispersión alcanza un límite fundamental, el límite de Planck, independiente de la dirección en cupratos.

Área De La Ciencia

  • Física de la materia condensada
  • Ciencias de los materiales
  • Los materiales cuánticos

Sus Antecedentes

  • Los metales convencionales exhiben una resistividad cuadrática dependiente de la temperatura.
  • Los metales extraños muestran una resistividad lineal con la temperatura, lo que sugiere un límite de dispersión fundamental.
  • Los orígenes de este límite de Planck en metales extraños siguen siendo en gran medida desconocidos.

Objetivo Del Estudio

  • Investigar los orígenes de la resistividad lineal en temperatura en metales extraños.
  • Medir la tasa de dispersión y sus propiedades en un material específico de cuprato.
  • Determinar si la tasa de dispersión se satura en el límite de Planck y su dependencia direccional.

Principales Métodos

  • Las mediciones de magnetorresistencia dependientes del ángulo en La1.6-xNdx0.4SrxCuO4.
  • Comparación cuantitativa con datos de espectroscopia de fotoemisión con resolución de ángulo.
  • Análisis de las tasas de dispersión de la carga portadora.

Principales Resultados

  • Confirmado una superficie de Fermi bien definida en el cuprato.
  • Se observó una tasa de dispersión lineal en temperatura saturada en el límite de Planck (α = 1,2 ± 0,4).
  • Encontró que la tasa de dispersión de Planck es isotrópica, contradiciendo los modelos de puntos calientes.

Conclusiones

  • La resistividad lineal en temperatura en metales extraños surge de la dispersión inelástica isotrópica, independiente del momento.
  • La velocidad de dispersión alcanza el límite fundamental de Planck.
  • Los hallazgos desafían los modelos teóricos existentes como los modelos de puntos calientes.

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