English
Related papers

Related papers: First-principles calculations for Fe impurities in…

200 papers

By studying Fe-doped ZnO pellets and thin films with various x-ray spectroscopic techniques, and complementing this with density functional theory calculations, we find that Fe-doping in bulk ZnO induces isovalent (and isostructural) cation…

Saturation magnetization values close to the bulk have been reported for coated magnetite nanoparticles with organic acids. The mechanism of this effect is not yet understood. Here we show that a previously proposed rationalization in Nano…

Materials Science · Physics 2022-01-05 Enrico Bianchetti , Cristiana Di Valentin

We propose a physics-informed neural network (PINN) model to efficiently predict the self-energy of Anderson impurity models (AIMs) based on the Lehmann representation. As an example, we apply the PINN model to a single-orbital AIM (SAIM)…

Strongly Correlated Electrons · Physics 2024-12-02 Fumiya Kakizawa , Satoshi Terasaki , Hiroshi Shinaoka

The impurity effects are studied for the BiS_{2}- layered superconductors based on a two orbital model with the Bogoliubov-de-Gennes technique. The superconducting critical temperature (T_{c}) as a function of the mpurity concentration is…

Superconductivity · Physics 2013-10-29 S. L. Liu

A reentrant temperature dependence of the thermoresistivity $\rho_{\mathrm{xx}}(T)$ between an onset local superconducting ordering temperature $T_\mathrm{loc}^\mathrm{onset}$ and a global superconducting transition at…

Thermodynamic properties are presented for four magnetic impurity models describing delocalized fermions scattering from a localized orbital at an energy-dependent rate $\Gamma(\epsilon)$ which vanishes precisely at the Fermi level,…

Strongly Correlated Electrons · Physics 2009-10-31 Carlos Gonzalez-Buxton , Kevin Ingersent

A new method is proposed for practical calculation of the effective interaction between impurity scatterers in superconductors, based on algebraic properties of related Nambu matrices for Green functions. In particular, we show that the…

Superconductivity · Physics 2009-11-10 Yu. G. Pogorelov , V. M. Loktev

Using the first-principles density-functional approach, magnetic properties of Mn-, Fe-, Co-, and Ni-doped rutile TiO2 were investigated for two different impurity concentrations (25% and 6.25%). Calculations were performed with the…

Materials Science · Physics 2008-04-24 L. A. Errico , M. Weissmann , M. Renteria

We illustrate the renormalized perturbation expansion method by applying it to a single impurity Anderson model. Previously, we have shown that this approach gives the {\it exact} leading order results for the specific heat, spin and charge…

Strongly Correlated Electrons · Physics 2009-11-07 A. C. Hewson

The electronic structure of the low-temperature (LT) monoclinic magnetite, Fe3O4, is investigated using the local spin density approximation (LSDA) and the LSDA+U method. The self-consistent charge ordered LSDA+U solution has a pronounced…

Strongly Correlated Electrons · Physics 2007-05-23 I. Leonov , A. N. Yaresko , V. N. Antonov , V. I. Anisimov

Quantum spin-orbital liquids are elusive strongly correlated states of matter that emerge from quantum frustration between spin and orbital degrees of freedom. A promising route towards the observation of those states is the creation of…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 Xu Dou , Valeri N. Kotov , Bruno Uchoa

Defects in graphene are of crucial importance for its electronic and magnetic properties. Here impurity effects on the electronic structure of surrounding carbon atoms are considered and the distribution of the local densities of states…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 T. O. Wehling , A. V. Balatsky , M. I. Katsnelson , A. I. Lichtenstein , K. Scharnberg , R. Wiesendanger

We have studied the effect of a single nonmagnetic impurity in the recently discovered (K,Tl)Fe$_x$Se$_2$ superconductors, within both a toy two-band model and a more realistic five-band model. We have found that, out of five types of…

Superconductivity · Physics 2015-05-27 Jian-Xin Zhu , Rong Yu , A. V. Balatsky , Qimiao Si

A complete Bethe Ansatz solution of the SU(N)xSU(f) Coqblin Schrieffer model and a detailed analysis of some physical applications of the model are given. As in the usual multichannel Kondo model a variety of Fermi liquid and non-Fermi…

Strongly Correlated Electrons · Physics 2009-10-31 Andres Jerez , Natan Andrei , Gergely Zarand

The low energy band structure of the FeAs based superconductors is fitted by a tight binding model with two Fe ions per unit cell and two degenerate orbitals per Fe ion. Based on this, superconductivity with extended s-wave pairing symmetry…

Superconductivity · Physics 2013-05-29 Degang Zhang

The effect of adding non-magnetic impurities (NMI), such as Zn or Li, to high-Tc cuprates is studied applying Monte Carlo techniques to a spin-fermion model. It is observed that adding Li is qualitatively similar to doping with equal…

Strongly Correlated Electrons · Physics 2009-10-31 Charles Buhler , Seiji Yunoki , Adriana Moreo

We report an ab initio study of the electric-field gradient tensor (EFG) at Cd impurities located at both inequivalent cationic sites in the semiconductor In2O3. Calculations were performed with the FLAPW method, that allows us to treat the…

Materials Science · Physics 2007-05-23 L. A. Errico , M. Renteria , G. Fabricius , G. N. Darriba

We study Kondo physics in the algebraic spin liquid, recently proposed to describe $ZnCu_{3}(OH)_{6}Cl_{2}$ [Phys. Rev. Lett. {\bf 98}, 117205 (2007)]. Although spin dynamics of the algebraic spin liquid is described by massless Dirac…

Strongly Correlated Electrons · Physics 2009-11-13 Ki-Seok Kim , Mun Dae Kim

Neutron scattering experiments have been carried out to explore Ni-impurity effects on static spin correlations in La2-xSrxCuO4 (LSCO) in the vicinity of the superconductor-insulator boundary where both parallel and diagonal spin-density…

Superconductivity · Physics 2007-05-23 H. Hiraka , S. Ohta , S. Wakimoto , M. Matsuda , K. Yamada

The spurious states found in numerical implementations of envelope function models for semiconductor heterostructures and nanostructures are artifacts of the use of the centered-difference formula. They are readily removed by employing a…

Mesoscale and Nanoscale Physics · Physics 2015-02-10 William R. Frensley , Raja N. Mir