2016/11/23 by Nikolay M. Plakida · 1 citation
Physics and Astronomy · #cond-mat.str-el
paper · pdf · doi:10.1016/j.physc.2016.10.002
published as Physica C: Superconductivity and its applications, V.531 (2016) 39 · 26 pages, 33 figures, 130 references. arXiv admin note: text overlap with arXiv:1301.4347, arXiv:1402.4934
arxiv created 2016/11/23 · arxiv updated 2016/12/21
To describe the cuprate superconductors, models of strongly correlated electronic systems, such as the Hubbard or t-J models, are commonly employed. To study these models, projected (Hubbard) operators have to be used. Due to the unconventional commutation relations for the Hubbard operators, a specific kinematical interaction of electrons with spin and charge fluctuations emerges. The interaction is induced by the intraband hopping with a coupling parameter of the order of the kinetic energy of electrons W which is much larger than the antiferromagnetic exchange interaction J induced by the interband hopping. This review presents a consistent microscopic theory of spin excitations and superconductivity for cuprates where these interactions are taken into account within the Hubbard operator technique. The low-energy spin excitations are considered for the t-J model, while the electronic properties are studied using the two-subband extended Hubbard model where the intersite Coulomb repulsion V and electron-phonon interaction are taken into account.