The Mott move in f electron frameworks, Pu, a dynamical mean field point of view.


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Build rough guesses to the useful G to perform reasonable figurings. ... of phonon frequencies in associated materials (S. Savrasov and G. Kotliar 2002) ...
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Slide 1

The Mott move in f electron frameworks, Pu, a dynamical mean field viewpoint Gabriel Kotliar Physics Department and Center for Materials Theory Rutgers University Collaborators: S. Savrasov (NJIT) ASR2002 Tokai Japan November 12-24 2002

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Mott move in the actinide arrangement (Smith Kmetko stage graph) THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Small measures of Ga balance out the d stage (A. Lawson LANL) THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Introduction: some Pu astounds. Prologue to DMFT. Some subjective bits of knowledge from model Hamiltonian contemplates. Towards and comprehension of natural Pu. Conclusions Outline THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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DFT in the LDA or GGA is a settled device for the computation of ground state properties. Numerous studies (Freeman, Koelling 1972)APW strategies ASA and FP-LMTO Soderlind et. Al 1990, Kollar et.al 1997, Boettger et.al 1998, Wills et.al. 1999) give a balance volume of the d stage Is 35% lower than investigation This is the biggest disparity ever known in DFT based estimations. Plutonium Puzzles THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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LSDA predicts attractive long range (Solovyev et.al.) Experimentally d Pu is not attractive. In the event that one regards the f electrons as a component of the center LDA overestimates the volume by 30% DFT in GGA predicts effectively the volume of the a period of Pu, when maximum capacity LMTO (Soderlind Eriksson and Wills) is utilized. This is typically taken as a sign that a Pu is a pitifully corresponded framework U/W is not all that distinctive in alpha and delta DFT Studies THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Pu Specific Heat THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Anomalous Resistivity THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Pu is NOT MAGNETIC THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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How to consider the alpha and delta stages and figure their physical properties? Why does delta have a negative warm development? Why do minute measure of pollutions stablize delta? Where does epsilon fit? Why is it littler than delta? Plutonium baffles. THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Introduction: some Pu astounds. Prologue to DMFT. Some subjective bits of knowledge from model Hamiltonian contemplates. Towards and comprehension of natural Pu. Conclusions Outline THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Mean-Field : Classical versus Quantum Classical case Quantum case A. Georges, G. Kotliar (1992) Phys. Rev. B 45, 6497 THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Renormalizing the quartic term in the nearby debasement activity. EDMFT. Taking a few destinations (groups) as neighborhood substance. CDMFT Combining DMFT with different strategies. LDA+DMFT, GWU. Expansions of DMFT. THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Identify noticeable, A. Develop a definite practical of <A>=a, G [a] which is stationary at the physical estimation of a. Develop approximations to the useful G to perform pragmatic estimations. Illustration: Density practical hypothesis (Fukuda et. al.),density, LDA, GGA. Illustration: model DMFT. Detectable: Local Greens capacity G ii ( w ). Precise useful G [G ii ( w ) ]. DMFT Approximation the useful keeping 2PI diagrams DMFT: compelling activity perspective. R. Chitra and G. Kotliar Phys. Rev. B 62, 12715 (2000), B63, 115110 (2001) THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Effective activity development. Present neighborhood orbitals, c a (r-R), and nearby GF G(R,R)(i w ) = The precise free vitality can be communicated as a practical of the nearby Greens capacity and of the thickness by presenting hotspots for (r) and G and performing a Legendre change, G[r (r),G(R,R)(i w )] S pectral Density Functionals for Electronic Structure Calculations, Sergej Savrasov and Gabriel Kotliar,  cond-mat/0106308 THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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The light, SP (or SPD) electrons are amplified, very much depicted by LDA The substantial, D (or F) electrons are localized,treat by DMFT. LDA as of now contains a normal collaboration of the substantial electrons, substract this out by moving the overwhelming level (twofold including term) The U lattice can be evaluated from first standards (Gunnarson and Anisimov, McMahan et.al. Hybertsen et.al) of saw as parameters Construct inexact practical which gives the LDA+DMFT mathematical statements. V. Anisimov, A. Poteryaev, M. Korotin, A.  Anokhin and G. Kotliar,  J. Phys. Cond. Mat. 35, 7359-7367 (1997) . THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Outer circle unwind E dc G 0 Impurity Solver Imp. Solver: Hartree-Fock G, S U SCC DMFT LDA+U THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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A. Georges G. Kotliar W. Krauth M. Rozenberg. Rev Mod Phys 68,1 (1996) Kotliar, Savrasov, in New Theoretical ways to deal with firmly related frameworks , Edited by A. Tsvelik, Kluwer Publishers, (2001). Held Nekrasov Blumer Anisimov and Vollhardt et.al. Int. Jour. of Mod PhysB15, 2611 (2001). A. Lichtenstein M. Katsnelson and G. Kotliar condmat 0211076(2002) Review THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Introduction: some Pu confounds. Prologue to DMFT. Some subjective bits of knowledge from model Hamiltonian examines. Towards and comprehension of essential Pu. Conclusions Outline THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Schematic DMFT stage chart one band Hubbard model (half filling, crescent DOS, halfway dissatisfaction) Rozenberg et.al PRL (1995) THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Cerium THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Spectral Evolution at T=0 , half filling full disappointment, Hubbard groups in the metal, exchange of otherworldly weight. X.Zhang M. Rozenberg G. Kotliar (PRL 1993) A. Georges, G. Kotliar (1992) Phys. Rev. B 45, 6497 THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Coexistence districts amongst limited and delocalized unearthly capacities. k separates at bland Mott endpoints Qualitative stage outline in the U, T , m plane (two band Kotliar Murthy Rozenberg PRL (2002). THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Minimum in liquefying bend and uniqueness of the compressibility at the Mott endpoint THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Cerium THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Generalized stage outline T U/W Structure, groups, orbitals THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Case study in f electrons, Mott move in the actinide arrangement. B. Johanssen 1974 Smith and Kmetko Phase Diagram 1984. THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Introduction: some Pu astounds. DMFT , subjective parts of the Mott move in model Hamiltonians. DMFT as an electronic structure strategy. DMFT results for delta Pu, and some subjective bits of knowledge. Conclusions Outline THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Snapshots of the f electron Dominant configuration:(5f) 5 Naïve view Lz=-3,- 2,- 1,0,1 ML=-5 m B S=5/2 Ms=5 m B Mtot=0 What is the predominant nuclear design? Nearby minute? THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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GGA+U groups. Savrasov Kotliar , Phys. Rev. Lett. 84, 3670-3673, (2000) THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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L=5, S=5/2, J=5/2, Mtot=Ms= m B gJ =.7 m B Crystal fields G 7 +G 8 GGA+U gauge (Savrasov and Kotliar 2000) ML=-3.9 Mtot=1.1 This bit is extinguished by Kondo impact of spd electrons [ DMFT treatment] Experimental result: neutrons extensive attractive field incited structure component (G. Lander). How is the Magnetic minute extinguished. THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Pu: DMFT all out vitality versus Volume S. Savrasov, G. Kotliar, and E. Abrahams, Nature 410, 793 (2001), THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Qualitative clarification of negative warm extension Double well structure and d Pu THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Delta and Alpha Pu are both emphatically connected, the DMFT mean field free vitality has a twofold well structure, for the same estimation of U. One where the f electron is more restricted (delta) than in the other (alpha). Is the common outcome of the model Hamiltonian stage chart once electronic structure is going to change. Dynamical Mean Field View of Pu ( Savrasov Kotliar and Abrahams, Nature 2001) THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Describes just the Hubbard groups. No QP states. Single well structure in the E versus V bend. (Savrasov and Kotliar PRL). Same in the event that one uses a Hubbard one polluting influence solver. Remarks on the HF static point of confinement for Pu THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Lda versus Exp Spectra THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Pu Spectra DMFT(Savrasov) EXP ( Arko Joyce Morales Wills Jashley PRB 62, 1773 (2000) THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Spectra Method E versus V Summary LDA LDA+U DMFT

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The high temperature stage, (epsilon) is body focused cubic, and has a littler volume than the (fcc) delta stage. What drives this stage move? A practical, that processes complete energies opens the path to the calculation of phonon frequencies in associated materials (S. Savrasov and G. Kotliar 2002) The delta –epsilon move THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Effects of structure. GGA+DMFT_Hubbard1 imp.solver e - E d =350 K GGA gives e - E d = - 6000 K THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Phonon freq (THz) versus q in delta Pu (S. Savrasov) THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Phonon recurrence (Thz ) versus q in epsilon Pu. THE STATE UNIVERSITY OF NEW JERSEY RUTGERS

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Compute the vitality of the

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