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Related papers: Doping Induced Spin State Transition in LaCoO3: Dy…

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We studied the Co valences and spin states in electron-doped LaCo$_{1-y}$Te$_{y}$O$_3$ by measuring x-ray absorption spectra and electron spin resonance. The low-temperature insulating state involves the low-spin Co$^{3+}$ ($S=0$) and the…

The spin state transition in LaCoO$_3$ has eluded description for decades despite concerted theoretical and experimental effort. In this study, we approach this problem using fully charge self-consistent Density Functional Theory + Embedded…

Materials Science · Physics 2017-11-15 Bismayan Chakrabarti , Turan Birol , Kristjan Haule

We have generalized the dynamical mean-field theory to study the doping dependence of the crossover from antiferromagnetic to short-range order modelled by an incommensurate spin density wave in the Hubbard model. The local selfenergy which…

Strongly Correlated Electrons · Physics 2009-10-31 M. Fleck , A. I. Lichtenstein , A. M. Oles , L. Hedin , V. I. Anisimov

Magnetic properties of Li$_x$CoO$_2$ for $x = 0.94, 0.75, 0.66$ and $0.51$ were investigated in frames of method combining Generalized Gradient Approximation with Dynamical Mean--Field Theory (GGA+DMFT). We found that a delicate interplay…

Strongly Correlated Electrons · Physics 2018-11-01 A. O. Shorikov , V. V. Gapontsev , S. V. Streltsov , V. I. Anisimov

The spin transition in LaCoO$_3$ has been investigated within the density-functional theory + dynamical mean-field theory formalism using continuous time quantum Monte Carlo. Calculations on the experimental rhombohedral atomic structure…

Strongly Correlated Electrons · Physics 2015-01-15 M. Karolak , M. Izquierdo , S. L. Molodtsov , A. I. Lichtenstein

The spin transition in LaCoO3 is investigated by temperature-dependent resonant soft X-ray emission spectroscopy near the Co 2p absorption edges. This element-specific technique is more bulk sensitive with respect to the temperature induced…

Strongly Correlated Electrons · Physics 2011-12-30 M. Magnuson , S. M. Butorin , C. Såthe , J. Nordgren , P. Ravindran

We investigate the spin state of LaCoO3 using state-of-the-art photoemission spectroscopy and ab initio band structure calculations. The GGA+U calculations provide a good description of the ground state for the experimentally estimated…

Strongly Correlated Electrons · Physics 2007-07-10 S. K. Pandey , Ashwani Kumar , S. Patil , V. R. R. Medicherla , R. S. Singh , K. Maiti , D. Prabhakaran , A. T. Boothroyd , A. V. Pimpale

In this paper a mean-field theory for the spin-liquid paramagnetic non-superconducting phase of the p- and n-type High-$T_c$ cuprates is developed. This theory applied to the effective $t-t'-t''-J^*$ model with the {\it ab initio}…

Strongly Correlated Electrons · Physics 2007-08-08 M. M. Korshunov , S. G. Ovchinnikov

We use the dynamical mean-field theory to study a p-d Hubbard Hamiltonian for LaCoO3 derived from ab initio calculations in local density approximation (LDA+DMFT scheme). We address the origin of local moments observed above 100 K and…

Strongly Correlated Electrons · Physics 2012-11-13 V. Křápek , P. Novák , J. Kuneš , D. Novoselov , Dm. M. Korotin , V. I. Anisimov

We present a nonperturbative method for deriving a quasiparticle description of the low-energy excitations in the t-J model for strongly correlated electrons. Using the exact diagonalization technique we evaluated exactly the spectral…

Condensed Matter · Physics 2009-10-22 R. Eder , Y. Ohta

Using numerical techniques we study the spectral function $A(k,\omega)$ of a spin-fermion model for cuprates in the regime where magnetic and charge domains (stripes) are developed upon hole-doping. From $A(k,\omega)$ we study the…

Superconductivity · Physics 2009-10-31 M. Moraghebi , C. Buhler , S. Yunoki , A. Moreo

A gradual spin-state transition occurs in LaCoO3 around T~80-120 K, whose detailed nature remains controversial. We studied this transition by means of inelastic neutron scattering (INS), and found that with increasing temperature an…

Strongly Correlated Electrons · Physics 2008-02-22 A. Podlesnyak , S. Streule , J. Mesot , M. Medarde , E. Pomjakushina , K. Conder , M. W. Haverkort , D. I. Khomskii

A fully ab initio scheme based on quantum chemical wavefunction methods is used to investigate the correlated multiorbital electronic structure of a 3d-metal compound, LaCoO3. The strong short-range electron correlations, involving both Co…

Strongly Correlated Electrons · Physics 2009-11-13 L. Hozoi , U. Birkenheuer , H. Stoll , P. Fulde

The unoccupied electronic states of LaCoO$_3$ and PrCoO$_3$ are studied using room temperature inverse photoemission spectroscopy and \emph{ab initio} GGA+$\emph{U}$ band structure calculations. A fairly good agreement between experiment…

Strongly Correlated Electrons · Physics 2008-03-25 S. K. Pandey , Ashwani Kumar , S. Banik , A. K. Shukla , S. R. Barman , A. V. Pimpale

Synchrotron X-ray powder diffraction experiments reveal that the transition from a magnetic intermediate spin (IS) state to a nonmagnetic low-spin (LS) ground state in LaCoO3 normally observed when cooling, manifests itself under pressure…

Materials Science · Physics 2009-11-07 T. Vogt , J. A. Hriljac , N. C. Hyatt , P. Woodward

Our success in description of recent electron-spin-resonance results on Mott insulator LaCoO3, Phys. Rev. B 67 (2003) 172401, lies in taking into account strong electron correlations among d electrons and the relativistic spin-orbit…

Strongly Correlated Electrons · Physics 2009-11-10 R. J. Radwanski , Z. Ropka

Lightly-doped La$_{2-x}$Sr$_x$CuO$_4$ in the so-called "insulating" spin-glass/diagonal-stripe phase has been studied by angle-resolved photoemission spectroscopy. A quasi-particle (QP) peak crossing the Fermi level has been observed in the…

The spin dynamics in single crystal, electron-doped Ba(Fe1-xCox)2As2 has been investigated by inelastic neutron scattering over the full range from undoped to the overdoped regime. We observe damped magnetic fluctuations in the normal state…

Superconductivity · Physics 2010-08-24 K. Matan , S. Ibuka , R. Morinaga , Songxue Chi , J. W. Lynn , A. D. Christianson , M. D. Lumsden , T. J. Sato

We propose a $d$-density wave induced by the spin-orbit coupling in the CuO plane. The spectral function of high-temperature superconductors in the under doped and lightly doped regions is calculated in order to explain the Fermi arc…

Strongly Correlated Electrons · Physics 2007-05-23 Takashi Yanagisawa , Mitake Miyazaki , Kunihiko Yamaji

We study the doping evolution of spin excitations in a 1D Hubbard model and its downfolded spin Hamiltonians, by using exact diagonalization combined with cluster perturbation theory. In all models, we observe hardening (softening) of spin…

Strongly Correlated Electrons · Physics 2019-05-08 Ekaterina M. Pärschke , Yao Wang , Brian Moritz , Thomas P. Devereaux , Cheng-Chien Chen , Krzysztof Wohlfeld
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