From Kondo to Anderson : time-dependent quantum transport through an interacting quantum dot within the Schwinger-Keldysh field theory formalism
This work delves into the theory of interacting electrons and local moment formation, modeled by the single impurity Anderson model (SIAM) and the Kondo effect, under the framework of nanoscale quantum transport theories. We explore the connection between these models through the Schrieffer-Wolff tr...
- Autores:
-
Fernández Sánchez, Jhoan Alexis
- Tipo de recurso:
- Trabajo de grado de pregrado
- Fecha de publicación:
- 2024
- Institución:
- Universidad del Valle
- Repositorio:
- Repositorio Digital Univalle
- Idioma:
- eng
- OAI Identifier:
- oai:bibliotecadigital.univalle.edu.co:10893/36043
- Acceso en línea:
- https://hdl.handle.net/10893/36043
- Palabra clave:
- Funciones de Green
Puntos cuánticos
Transporte cuántico
Electrones interactuantes
- Rights
- openAccess
- License
- https://creativecommons.org/licenses/by-nc-nd/4.0/
| Summary: | This work delves into the theory of interacting electrons and local moment formation, modeled by the single impurity Anderson model (SIAM) and the Kondo effect, under the framework of nanoscale quantum transport theories. We explore the connection between these models through the Schrieffer-Wolff transformation (SWT) and study time-dependent quantum transport through an interacting quantum dot, serving as a bridge between practical quantum transport systems and the Kondo model. Using the intricate Schwinger-Keldysh nonequilibrium Green’s functions (NEGF) technique, we investigate the system’s response to a bias voltage applied to metallic leads, analyzing the Jauho-Meir-Wingreen (JMW) charge current within stationary and wide- band limit (WBL) approximations. Applying the non-canonical Hubbard-I approximation to the electron-electron interaction term, we derived analytical expressions for the time-dependent charge current and electron spin occupation through the quantum dot for different Coulomb interaction strengths between electrons. The results obtained align well with previously reported literature and reveal enhanced mean-field correlation effects on the charge dynamics while assessing the model’s capacity to describe Kondo effects in transport phenomena. This study lays the groundwork for more realistic models and paves the way for advanced theoretical and computational approaches in the quantum transport unit of the theoretical solid-state physics group at Universidad del Valle. |
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