Ferromagnetic fluctuations in the Rashba-Hubbard model

We study the occurrence and the origin of ferromagnetic fluctuations in the longitudinal spin susceptibility of the t-t′-Rashba-Hubbard model on the square lattice. The combined effect of the second-neighbor hopping t′ and the spin-orbit coupling leads to ferromagnetic fluctuations in a broad fillin...

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Detalles Bibliográficos
Autores: Greco, Andrés, Bejas, Matias Hector, Schnyder, Andreas P.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/143740
Acceso en línea:http://hdl.handle.net/11336/143740
Access Level:acceso abierto
Palabra clave:Rashba-Hubbard model
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:We study the occurrence and the origin of ferromagnetic fluctuations in the longitudinal spin susceptibility of the t-t′-Rashba-Hubbard model on the square lattice. The combined effect of the second-neighbor hopping t′ and the spin-orbit coupling leads to ferromagnetic fluctuations in a broad filling region. The spin-orbit coupling splits the energy bands, leading to two Van Hove fillings, where the sheets of the Fermi surface change their topology. Between these two Van Hove fillings the model shows ferromagnetic fluctuations. We find that these ferromagnetic fluctuations originate from interband contributions to the spin susceptibility. These interband contributions only arise if there is one holelike and one electronlike Fermi surface, which is the case for fillings in between the two Van Hove fillings. We discuss implications for experimental systems and propose a test on how to identify these types of ferromagnetic fluctuations in experiments.