Thermal entanglement witness for materials with variable local spin lengths

• Autor(a) principal: Souza, André Maurício Conceição de
• Data de Publicação: 2009
• Outros Autores: Almeida, Francisco A. G.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFS
• DOI: 10.1103/PhysRevA.79.052337
• Texto Completo: https://ri.ufs.br/handle/riufs/477
• topic: Termodinâmica; Modelo de Hubbard

We show that the thermal entanglement in a spin system using only magnetic-susceptibility measurements is restricted to the insulator materials. We develop a generalization of the thermal entanglement witness that allows us to get information about the system entanglement with variable local spin lengths that can be used experimentally in conductor or insulator materials. As an application, we study thermal entanglement for the half-filled Hubbard model for linear, square, and cubic clusters. We note that it is the itinerancy of electrons that favors the entanglement. Our results suggest a weak dependence between entanglement and external spin freedom degrees.