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La ley de Wiedemann-Franz en aislantes Mott dopados sin cuasipartículas
Wen O Wang1,2, Jixun K Ding1,2, Yoni Schattner2,3,4
1Department of Applied Physics, Stanford University, Stanford, CA 94305, USA.
Science (New York, N.Y.)
|November 30, 2023
Resumen
Los materiales cuánticos exhiben propiedades de transporte inusuales. Nuestro estudio revela que el transporte a baja temperatura en aislantes Mott dopados se acerca a la ley de Wiedemann-Franz, ofreciendo ideas más allá de las teorías tradicionales.
Área de la Ciencia:
- Física de la materia condensada
- Ciencia de los materiales cuánticos
Sus antecedentes:
- Muchos materiales cuánticos metálicos muestran transporte anómalo, desviándose de la teoría del líquido de Fermi.
- Comprender estos fenómenos es crucial para el desarrollo de nuevos dispositivos electrónicos.
Objetivo del estudio:
- Para investigar el transporte térmico y de carga en el modelo de Hubbard.
- Para analizar el cruce entre los comportamientos de alta y baja temperatura en materiales cuánticos.
Principales métodos:
- Cálculos numéricos del transporte térmico y de carga.
- Análisis del número de Lorenz (L) y su dependencia del dopaje.
- Descomposición del operador de corriente de energía.
Principales resultados:
- Se observó un cruce que separa los comportamientos de alta y baja temperatura.
- A bajas temperaturas, el número de Lorenz (L) se vuelve débilmente dependiente del dopaje y se acerca a la constante de Wiedemann-Franz (L0).
- Este comportamiento persiste incluso en aislantes Mott dopados que carecen de cuasipartículas bien definidas.
Conclusiones:
- El estudio aclara los mecanismos de transporte en metales fuertemente correlacionados.
- Los resultados sugieren una compensación entre las contribuciones de energía cinética y potencial a la corriente.
- Este trabajo proporciona un marco para interpretar experimentos de transporte más allá de la teoría de Boltzmann.
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