English
Related papers

Related papers: Quantitative Aspects of the Dynamical CPA in Harmo…

200 papers

We present here the first-principles dynamical CPA (coherent potential approximation) combined with the tight-binding LMTO LDA+U method towards quantitative calculations of the electronic structure and magnetism at finite temperatures in…

Strongly Correlated Electrons · Physics 2015-05-14 Y. Kakehashi , T. Tamashiro , M. A. R. Patoary , T. Nakamura

Dynamical Coherent-Potential Approximation (CPA) to correlated electrons has been extended to a system with realistic Hamiltonian which consists of the first-principles tight-binding Linear Muffintin Orbital (LMTO) bands and intraatomic…

Strongly Correlated Electrons · Physics 2008-07-08 Y. Kakehashi , T. Shimabukuro , T Tamashiro , T. Nakamura

First-principles dynamical CPA (Coherent-Potential Approximation) for electron correlations has been developed further by taking into account higher-order dynamical corrections with use of the asymptotic approximation. The theory is applied…

Strongly Correlated Electrons · Physics 2015-05-19 Y. Kakehashi , M. Atiqur R. Patoary , T. Tamashiro

Magnetic properties of Fe, Co, and Ni at finite temperatures have been investigated on the basis of the first-principles dynamical CPA (Coherent Potential Approximation) combined with the LDA (Local Density Approximation) + $U$ Hamiltonian…

Strongly Correlated Electrons · Physics 2015-05-27 Yoshiro Kakehashi , M. Atiqur R. Patoary

The DCA$^+$ algortihm was recently introduced to extend the dynamic cluster approximation (DCA) with a continuous lattice self-energy in order to achieve better convergence with cluster size. Here we extend the DCA$^+$ algorithm to the…

Strongly Correlated Electrons · Physics 2015-06-18 Peter Staar , Thomas Maier , Thomas Schulthess

The infinite-dimensional Hubbard model is studied by means of a modified perturbation theory. The approach reduces to the iterative perturbation theory for weak coupling. It is exact in the atomic limit and correctly reproduces the…

Strongly Correlated Electrons · Physics 2009-10-30 T. Wegner , M. Potthoff , W. Nolting

Using a combined local density functional theory (LDA-DFT) and quantum Monte Carlo (QMC) dynamic cluster approximation approach, the parameter dependence of the superconducting transition temperature Tc of several single-layer hole-doped…

Quantum Monte Carlo (QMC) simulations and the Local Density Approximation (LDA) are used to map the constant particle number (canonical) trajectories of the Bose Hubbard Hamiltonian confined in a harmonic trap onto the $(\mu/U,t/U)$ phase…

Other Condensed Matter · Physics 2009-11-13 G. G. Batrouni , H. R. Krishnamurthy , K. W. Mahmud , V. G. Rousseau , R. T. Scalettar

We formulate a finite-temperature scheme of the variational cluster approximation (VCA) particularly suitable for an exact-diagonalization cluster solver. Based on the analytical properties of the single-particle Green's function matrices,…

Strongly Correlated Electrons · Physics 2018-11-09 Kazuhiro Seki , Tomonori Shirakawa , Seiji Yunoki

We employ dynamical mean field theory (DMFT) with a Quantum Monte Carlo (QMC) atomic solver to investigate the finite temperature Mott transition in the Hubbard model with the nearest neighbor hopping on a triangular lattice at…

Strongly Correlated Electrons · Physics 2009-11-11 K. Aryanpour , W. E. Pickett , R. T. Scalettar

Previously a many-body coherent potential approximation (CPA) was used to study the double exchange (DE) model with quantum local spins S, both for S=1/2 and for general S in the paramagnetic state. This approximation, exact in the atomic…

Strongly Correlated Electrons · Physics 2009-10-31 A. C. M. Green , D. M. Edwards

The local moment approach (LMA) has presented itself as a powerful semi-analytical quantum impurity solver (QIS) in the context of the dynamical mean-field theory (DMFT) for the periodic Anderson model and it correctly captures the low…

Strongly Correlated Electrons · Physics 2016-07-13 Himadri Barman

We investigate the Hubbard model on the triangular lattice at half-filling using the dynamical cluster approximation (DCA) and dual fermion (DF) methods in combination with continuous-time quantum Monte carlo (CT QMC) and semiclassical…

Strongly Correlated Electrons · Physics 2009-11-13 Hunpyo Lee , Gang Li , Hartmut Monien

Correlation effects play an important role in the electronic structure of half-metallic (HM) magnets. In particular, they give rise to non-quasiparticle states above (or below) the Fermi energy at finite temperatures that reduce the spin…

Strongly Correlated Electrons · Physics 2015-06-17 Ersoy Sasioglu , Iosif Galanakis , Christoph Friedrich , Stefan Blügel

We present the algorithmic details of the dynamical cluster approximation (DCA), with a quantum Monte Carlo (QMC) method used to solve the effective cluster problem. The DCA is a fully-causal approach which systematically restores non-local…

Strongly Correlated Electrons · Physics 2009-11-07 M. Jarrell , Th. Maier , C. Huscroft , S. Moukouri

The Hubbard model on fcc-type lattices is studied in the dynamical mean-field theory of infinite spatial dimensions. At intermediate interaction strength finite temperature Quantum Monte Carlo calculations yield a second order phase…

Strongly Correlated Electrons · Physics 2009-10-30 Martin Ulmke

We propose a new treatment of the Hubbard model that is based both on the coherent-potential approximation (CPA) and the virtual-crystal approximation (VCA). It is well known that the equilibrium found using the one-particle CPA Green's…

Strongly Correlated Electrons · Physics 2007-05-23 A. Uldry , R. J. Elliott

We study the three-band Hubbard model for the copper oxide plane of the high-temperature superconducting cuprates using determinant quantum Monte Carlo and the dynamical cluster approximation (DCA) and provide a comprehensive view of the…

Superconductivity · Physics 2021-04-28 Peizhi Mai , Giovanni Balduzzi , Steven Johnston , Thomas A. Maier

We present clear numerical evidence for the coexistence of metallic and insulating dynamical mean field theory(DMFT) solutions in a half-filled single-band Hubbard model with bare semicircular density of states at finite temperatures.…

Strongly Correlated Electrons · Physics 2009-10-31 Jaewook Joo , Viktor Oudovenko

We study the exchange interactions in half-metallic Heusler alloys using first-principles calculations in conjunction with the frozen-magnon approximation. The Curie temperature is estimated within both mean-field (MF) and…

Materials Science · Physics 2009-11-11 E. Sasioglu , L. M. Sandratskii , P. Bruno , I. Galanakis
‹ Prev 1 2 3 10 Next ›