Thermoelectric properties of a double quantum dot out of equilibrium in Kondo and intermediate valence regimes

We study a system composed of two quantum dots connected in series between two leads at different temperatures, in the limit of large intratomic repulsion. Using the non-crossing approximation, we calculate the spectral densities at both dots ρi(ω), the thermal and thermoelectric responses, thermopo...

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Detalles Bibliográficos
Autores: Perez Daroca, Diego Raul, Roura Bas, Pablo Gines, Aligia, Armando Angel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/223613
Acceso en línea:http://hdl.handle.net/11336/223613
Access Level:acceso abierto
Palabra clave:Thermopower
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:We study a system composed of two quantum dots connected in series between two leads at different temperatures, in the limit of large intratomic repulsion. Using the non-crossing approximation, we calculate the spectral densities at both dots ρi(ω), the thermal and thermoelectric responses, thermopower and figure of merit in different regimes. The interatomic repulsion leads to finite heat transport even if the hopping between the dots t = 0. The thermopower can be very large compared to single-dot systems in several regimes. The changes in sign of the thermoelectric current can be understood from the position and magnitude of the Kondo and charge-transfer peaks in ρi(ω). The figure of merit can reach values near 0.7. The violation of the Wiedemann-Franz law is much more significant than in previously studied nanoscopic systems. An analysis of the widths of ρi(ω) indicates that the dots are at effective temperatures Ti intermediate between those of the two leads, which tend to be the same for large t.