Zobrazeno 1 - 10
of 49
pro vyhledávání: '"Raimundo R. dos Santos"'
Publikováno v:
Physical Review Research, Vol 2, Iss 3, p 033168 (2020)
The nature of superconductivity in heavy-fermion materials is a subject under intense debate, and controlling this many-body state is central for its eventual understanding. Here, we examine how proximity effects may change this phenomenon, by invest
Externí odkaz:
https://doaj.org/article/dc303a0a0d2f41fcada43ac190a598ed
Autor:
Andrea Tirelli, Danyella O. Carvalho, Lucas A. Oliveira, José P. de Lima, Natanael C. Costa, Raimundo R. dos Santos
Publikováno v:
The European Physical Journal B. 95
In this paper with study phase transitions of the $q$-state Potts model, through a number of unsupervised machine learning techniques, namely Principal Component Analysis (PCA), $k$-means clustering, Uniform Manifold Approximation and Projection (UMA
Publikováno v:
Journal of Magnetism and Magnetic Materials. 423:74-83
We study the Kondo Lattice Model (KLM) on a square lattice through a Hartree-Fock approximation in which the local spins are treated semi-classically, in the sense that their average values are modulated by a magnetic wavevector $\mathbf{Q}$ while th
The Kondo and Periodic Anderson models describe many of the qualitative features of local moments coupled to a conduction band, and thereby the physics of materials such as the heavy fermions. In particular, when the exchange coupling $J$ or hybridiz
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5ff067111c595cfc243e58cd80fe787a
Autor:
Natanael C. Costa, Raimundo R. dos Santos, Tiago Mendes-Santos, Richard T. Scalettar, Thereza Paiva
The noninteracting electronic structures of tight binding models on bipartite lattices with unequal numbers of sites in the two sublattices have a number of unique features, including the presence of spatially localized eigenstates and flat bands. Wh
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d3157d6a7fed0bf0bce4774ee0c487c0
Publikováno v:
Physical Review A. 91
We investigate the harmonic-trap control of size and shape of Mott regions in the Fermi Hubbard model on a square optical lattice. The use of Lanczos diagonalization on clusters with twisted boundary conditions, followed by an average over 50-80 samp
Publikováno v:
ResearcherID
A theoretical study of the effects of disorder on the Mn-Mn exchange interactions for Ga1-xMnxAs diluted magnetic semiconductors is presented. The disorder is intrinsically considered in the calculations, which are performed using an ab initio total
Publikováno v:
Journal of Physics: Condensed Matter. 16:8243-8250
We have performed ab initio calculations within the density-functional theory for Ga1−xMnxAs diluted semiconductors. Total energy results unambiguously show that a quasi-localized hole, with predominant p-like character, surrounds the fully polariz
Publikováno v:
Physica B: Condensed Matter. :874-877
We perform a detailed theoretical study, within the density-functional theory, of the electronic structure and magnetic properties of Ga1−xMnxAs diluted semiconductors. Ab initio total energy results provide evidence that the appearance of a ferrom
Publikováno v:
Journal of Physics: Condensed Matter. 15:7917-7924
We propose a superlattice model to describe superconductivity in layered materials, such as the borocarbide families with the chemical formul\ae\ $RT_2$B$_2$C and $RT$BC, with $R$ being (essentially) a rare earth, and $T$ a transition metal. We assum