Dynamical Mean-Field Theory for Correlated Electron Materials Dieter Vollhardt
|
|
- Grant Walker
- 5 years ago
- Views:
Transcription
1 Center for Electronic Correlations and Magnetism University of Augsburg Dynamical Mean-Field Theory for Correlated Electron Materials Dieter Vollhardt XXIII Latin American Symposium on Solid State Physics Bariloche, Argentina; April 12, 2018
2 Outline: 1. Electronic correlations 2. Dynamical mean-field theory (DMFT) 3. DFT+DMFT: Ab initio approach to correlated electron materials 4. Applications: - Fe: Correlation induced lattice stability - FeSe: Phase stability and Lifshitz transitions
3 Correlations
4 Correlation [lat.] (con + relatio): mutual relation, interdependence Temporal/spatial correlations in every-day life correlated many-particle system
5 Correlation [lat.] (con + relatio): mutual relation, interdependence Temporal/spatial correlations in every-day life correlated many-particle system factorization!?
6 Electronic correlations
7 Electronic Correlations in Solids Narrow d,f-bands electronic correlations important
8 Definition of electronic correlations (I) Correlations = effects beyond Hartree Fock / single-particle (product) wave functions nn ˆˆ ˆ ˆ i j ni nj quantifies correlations - Hartree-Fock: Particle interacts with a self-consistent potential - LDA/GGA of density functional theory (DFT) Many-body effects ( correlations ): Particle interacts with all other particles at (r i,t) single-particle excitations in general unknown But Single-particle states (k-states)? yes, no (in general) Landau lifetime τ = quasiparticles: yes, τ <
9 Fermi gas: Excited state k z Particle Fermi surface Hole k y k x Fermi sphere k-eigenstates: infinite life time Switch on repulsive interaction unsolvable many-body problem
10 Fermi liquid Standard model of condensed matter physics Fermi surface k z (Quasi-) Hole Landau (1956/58) 1-1 correspondence between single-particle states (k,σ) (Quasi-) Particle = elementary excitation k y k x Fermi sphere Microscopic derivation by diagrammatic perturbation theory to all orders Abrikosov, Khalatnikov (1959)
11 Unusual properties of correlated electron materials huge resistivity changes gigantic volume anomalies colossal magnetoresistance high-t c superconductivity metallic behavior at interfaces of insulators, With potential for technological applications: sensors, switches spintronics thermoelectrics high-t c superconductor devices functional materials: oxide heterostructures,
12 Theoretical approaches Gutzwiller, 1963 Correlated material strongest simplification Þ Hubbard model Hubbard, 1963 Kanamori, 1963 time U H = t c c + U n n ij,, σ iσ jσ i i i n n n n i i i i Theoretical challenge of many-fermion problems: Construct comprehensive, controlled, non-perturbative approximation schemes
13 Non-perturbative approximation schemes for real materials, GGA How to combine? time U Held (2004)
14 Dynamical mean-field theory (DMFT) for correlated electrons
15 Limit d or Z H = t c c + U n n ij,, σ for lattice electrons iσ jσ i i i Hubbard model Face-centered cubic lattice (d=3) U time Metzner, DV (1989) dz, Strong simplifications in many-body theory dynamical mean field Z=12 Self-consistent single-impurity Anderson model Georges, Kotliar (1992)
16 Dynamical mean-field theory (DMFT) of correlated electrons Σ( k, ω) Σ( ω) U Kotliar, DV (2004) Exact treatment of many-body dynamics Microscopic derivation by diagrammatic perturbation theory to all orders Φ-derivable, thermodynamically consistent, conserving
17 Dynamical mean-field theory (DMFT) of correlated electrons Σ( k, ω) Σ( ω) U Kotliar, DV (2004) Itinerant fermions Spectral function E d -U/2 E d U E d +U/2 E U
18 Dynamical mean-field theory (DMFT) of correlated electrons Σ( k, ω) Σ( ω) U Kotliar, DV (2004) Itinerant fermions Spectral function Single-particle excitations (Landau quasiparticles), not electrons U
19 Dynamical mean-field theory (DMFT) of correlated electrons Σ( k, ω) Σ( ω) U Kotliar, DV (2004) Itinerant fermions Spectral function U Definition of electronic correlations (II): transfer of spectral weight [due to Re (ω)] finite lifetime of excitations [due to Im (ω)] Experimentally detectable (ARPES, )
20 Computational scheme for correlated electron materials: Material specific electronic structure (Density functional theory: LDA, GGA,...) + Local electronic correlations (Many-body theory: DMFT) = LDA+DMFT Anisimov et al. (1997) Lichtenstein, Katsnelson (1998) Held et al. (2003) Kotliar et al. (2006)
21 Computational scheme for correlated electron materials: Material specific electronic structure (Density functional theory: LDA, GGA,...) or GW + Local electronic correlations (Many-body theory: DMFT) = X+DMFT X= DFT (LDA, GGA); GW,
22 Effective multi-orbital Anderson impurity model with self-consistency condition Σ(ω) i G( ω) (i) Effective single impurity problem (ii) k-integrated Dyson equ. Solve self-consistently with an impurity solver, e.g., QMC, CT-QMC, NRG, DMRG, ED If correlations strongly redistribute charge density need also charge self-consistency e.g., V 2 O 3 : Mott transition with lattice distortion Leonov, Anisomov, DV (2015)
23 Spectral functions in DMFT k-integrated spectral function ( interacting DOS ) PES 1 A( ω) = Im G( ω) π k-resolved spectral function ARPES G( k, ω) = [ ω Σ( ω) H ( k)] 0 1 LDA 1 A( k, ω) = I mtrg( k, ω) π
24 Held, Nekrasov, Keller, Eyert, Blümer, McMahan, Scalettar, Pruschke, Anisimov, DV (Psi-k, 2003)
25 Until ~ 10 years ago: Theoretical investigations of electronic correlations in materials for given lattice structure La O Mn e g electrons Pnma primitive cell of paramagnetic LaMnO 3 How do electronic correlations influence the stability of the ionic lattice?
26 Application of GGA+DMFT to Fe Most abundant element by mass on Earth Ferromagnetism with very high T C Most widely used metal in modern day industry ( iron age )
27 Electronic Correlations in Solids Narrow d,f-bands electronic correlations important Fe: Electronic configuration [Ar] 3d 6 4s 2
28 DMFT: Ferromagnetism in the one-band Hubbard model Generalized fcc lattice ( Z ) Ulmke (1998) Ferromagnetic order of itinerant local moments Curie-Weiss T C LDA+DMFT Lichtenstein, Katsnelson, Kotliar (2001) Microscopic origin of exchange interactions in Fe Eriksson collaboration (2016)
29 Structural stability of Fe Collaborators: Ivan Leonov (Augsburg, Ekaterinburg) Alexander Poteryaev (Ekaterinburg) Vladimir Anisimov (Ekaterinburg) α-γ structural phase transition in paramagnetic iron: Leonov et al., Phys. Rev. Lett. 106, (2011) Phonons: Leonov et al., Phys. Rev. B 85, (R) (2012) Phase stability up to melting: Leonov et al., Sci. Rep. 4, 5585 (2014)
30 Fe austenite ferrite hexaferrum Exceptional: Abundance of allotropes: α, γ, δ, ε, phases Very high Curie temperature (T C = 1043 K) bcc-phase stable for P,T 0
31 Fe austenite ferrite hexaferrum Abrikosov collaboration (2007) Lawrence Livermore National Laboratory
32 Fe T struct austenite ferrite hexaferrum DFT(GGA): finds paramagnetic bcc phase to be unstable - What stabilizes paramagnetic ferrite? - What causes the bcc-fcc structural phase transition?
33 bcc-fcc structural transition in paramagnetic Fe Goal: Understand the structural stability of paramagnetic bcc phase Construct Wannier functions for partially filled Fe sd orbitals Pressure, GPa First-principles multi-band Hamiltonian including local interactions Coulomb interaction between Fe 3d electrons: U=1.8 ev, J=0.9 ev
34 bcc-fcc structural transition in paramagnetic Fe Goal: Understand the structural stability of paramagnetic bcc phase Construct Wannier functions for partially filled Fe sd orbitals Pressure, GPa GGA+DMFT total energy E tot - E bcc GGA: Only paramagnetic fcc structure stable GGA+DMFT: bcc-fcc structural transition at T struct 1.3 T C Conclusion: Paramagnetic α-phase stabilized by electronic correlations bcc fcc Bain transformation path Leonov, Poteryaev, Anisimov, DV (2011)
35 bcc-fcc structural transition in paramagnetic Fe Equilibrium volume V Equilibrium volume (au 3 ) GGA+DMFT bcc Fe V ~ -2% fcc Fe Non-magnetic GGA: V ~ 141/138 au 3 in bcc/fcc phase too small density too high GGA+DMFT: Pressure, GPa V ~ 161.5/158.5 au 3 in bcc/fcc phase increased by electronic repulsion Leonov, Poteryaev, Anisimov, DV (2011) Agrees well with exp. data: V exp ~ 165 / 158 au 3 Conclusion: bcc-fcc structural transition caused by electronic correlations
36 Lattice dynamics and phonon spectra of Fe
37 Lattice dynamics of paramagnetic bcc iron Non-magnetic GGA: Phonon dispersion Pressure, GPa 1. Brillouin zone Dynamically unstable + elastically unstable (C 11, C < 0) Exp.: Neuhaus, Petry, Krimmel (1997) What stabilizes the phonons?
38 Lattice dynamics of paramagnetic bcc iron phonon frequencies calculated with frozen-phonon method harmonic approximation Stokes, Hatch, Campbell (2007) Pressure, GPa GGA+DMFT: Phonon dispersion at 1.2 T C Calculated: equilibrium lattice constant a~2.883 Å (a exp ~2.897 Å) Debye temperature Θ~458 K Leonov, Poteryaev, Anisimov, DV (2012) Exp.: Neuhaus, Petry, Krimmel (1997) Conclusion: Phonons in bcc iron stabilized by electronic correlations
39 Application of GGA+DMFT to FeSe Collaborators: Ivan Leonov (Augsburg, Ekaterinburg) Sergey Skornyakov (Ekaterinburg) Vladimir Anisimov (Ekaterinburg) FeSe (expansion): Leonov et al., Phys. Rev. Lett. 115, (2015) Skornyakov et al., Phys. Rev. B 96, (2017) FeSe (compression): Skornyakov et al., Phys. Rev. B 97, (2018)
40 Electronic Correlations in Solids Narrow d,f-bands electronic correlations important
41 Fe-based superconductors Kamihara et al. (2008) Si, Yu, Abrahams (2016) 11 FeSe 111 LiFeAs 1111 LaFeAsO 122 CaFe 2 As 2 Layered structure, but no separating layers Superconductivity induced by doping or pressure
42 FeSe: Crystal structure and properties Tetragonal (PbO-structure): α-fese T c = 8 K ( 37 K under hydrostatic pressure) Isovalent substitution Se Te (lattice expansion) T c increases up to 14 K Increase of T c under expansion and compression! FeSe FeSe 1-x Te x, x<0.7 FeTe no static magnetic order, short-range fluctuations with Q m =(π, π) T N ~ 70 K Q m =(π, 0) T c ~ 8 K T c ~ 14 K - Why does the electronic and magnetic structure of Fe(Se,Te) change with lattice expansion or compression?
43 FeSe: Phase stability under expansion Non-charge-self-consistent calculation (ncsc) Fully charge-self-consistent calculation (csc) Leonov et al. (2015) Skornyakov et al. (2017) Partially filled Fe 3d, Se 4p orbitals; Coulomb interaction Fe 3d: σσ U : U = 3.5 ev, J = 0.85eV mm lattice constant a (a.u.), c/a fixed csc results: Isostructural transformation upon ~ 13% lattice expansion (p c = 7.6 GPa) GGA vs. GGA+DMFT total energy lattice anomaly equilibrium structure: a = 7.05 a.u. expanded structure: a = 7.6 a.u.
44 FeSe: Phase stability and local moment under expansion Non-charge-self-consistent calculation (ncsc) Fully charge-self-consistent calculation (csc) Leonov et al. (2015) Skornyakov et al. (2017) lattice constant a (a.u.), c/a fixed csc results: Isostructural transformation upon ~ 13% lattice expansion (p c = 7.6 GPa) Strong increase of the fluctuating local magnetic moment + compressibility Equilib. volume (a = 7.05 a.u.) Expanded volume (a = 7.6 a.u.) B = 79 GPa 49 GPa μμ 2 zz = 1.9 µ B 2.9 µ B Observed in FeTe: Suppression of magnetism under 4-6 GPa Exp: Zhang et al. (2009)
45 FeSe upon expansion Spectral function Electronic structure Fermi surface
46 FeSe: Spectral function Leonov et al. (2015) Skornyakov et al. (2017) Van Hove singularity shifts to E F due to correlations equilibrium volume a = 7.05 a.u. Expansion Suppression of spectral weight expanded volume a = 7.6 a.u. Similar results: Watson, Backes, Haghighirad, Hoesch, Kim, Coldea, Valenti (2017)
47 FeSe: Spectral function Leonov et al. (2015) Skornyakov et al. (2017) Van Hove singularity shifts to E F due to correlations equilibrium volume a = 7.05 a.u. Expansion expanded volume a = 7.6 a.u. Exp.: Yokoya et al. (2012) Spectral weight suppressed with Te substitution ( = lattice expansion)
48 FeSe: Electronic structure Leonov et al. (2015) Skornyakov et al. (2017) non-magnetic GGA GGA+DMFT Expansion Equilibrium volume: Quasiparticle bands renormalized + orbital-selective shift Van Hove singularity at M point pushed towards E F Expanded volume: Complete change of electronic structure Correlation-induced shift of Van Hove singularity above E F
49 FeSe: Fermi surface Leonov et al. (2015) Skornyakov et al. (2017) non-magnetic GGA GGA+DMFT Expansion Equilibrium volume: Correlations do not change FS In-plane nesting with Q m =(π,π) Expanded volume: Correlations change FS topology (Lifshitz transition) Electron pocket at M point vanishes In-plane nesting with Q m =(π,0) Conclusion: Change of magnetic structure upon lattice expansion caused by correlations In accord with ARPES experiments on FeSe 1-x Te x Chen et al. (2010), Zhang et al. (2010), Jiang et al. (2013), Liu et al. (2013,2015), Nakayama et al. (2010,2014)
50 FeSe: Behavior under compression Skornyakov et al. (2018) DFT+DMFT with structural optimization (V, c/a, z Se ) Dependence of Fermi surface on pressure, T=290 K ambient pressure 10 GPa k z =0 plane k x =k y plane k x k=k x y weak k z dependence k x =k y sizable k z dependence Upon compression: (i) Band degeneracy lifted (orbital dependence) (ii) 2d-3d transition (Lifshitz transition) (iii) χ(q): Reduction of spin fluctuations and (π,π) nesting
51 FeSe: Behavior under compression Skornyakov et al. (2018) DFT+DMFT with structural optimization (V, c/a, z Se ) Dependence of Fermi surface on pressure, T=290 K ambient pressure 10 GPa k z =0 plane k x =k y plane k x k=k x y weak k z dependence k x =k y sizable k z dependence Conjecture: - Compression-induced increase of T c due to phonons - Expansion-induced increase of T c due to spin fluctuations
52 FeSe: Size of Fermi surface pockets? Experiment GGA or GGA+DMFT Watson et al. (2017) Size of pockets smaller than in GGA or GGA+DMFT due to - non-local correlations? - frustrated magnetism? - spin-orbit coupling? Leonov et al. (unpublished, 2015)
53 Conclusion 1) DFT+DMFT: powerful tool to study/predict properties of correlated materials 2) Electronic correlations strongly influence the electronic properties + phase stability of materials 3) DFT+DMFT codes publically available VASP-DMFT code probably available later in 2018
Surprising Effects of the Interaction between Electrons in Solids. Dieter Vollhardt
Surprising Effects of the Interaction between Electrons in Solids Dieter Vollhardt Shanghai Jiao Tong University; April 6, 2016 Augsburg: founded in 15 BC Roman Emperor Augustus 63 BC 14 AD Center founded
More informationFrom Materials to Models and Back. Dieter Vollhardt
From Materials to Models and Back Dieter Vollhardt 28 th Edgar Lüscher Seminar, Klosters; February 8, 2017 From Materials to Models and Back - The Need for Models in Condensed Matter Physics - Outline:
More informationSurprising Effects of Electronic Correlations in Solids
Center for Electronic Correlations and Magnetism University of Augsburg Surprising Effects of Electronic Correlations in Solids Dieter Vollhardt Supported by TRR 80 FOR 1346 University of Florida, Gainesville;
More informationFrom Gutzwiller Wave Functions to Dynamical Mean-Field Theory
From utzwiller Wave Functions to Dynamical Mean-Field Theory Dieter Vollhardt Autumn School on Correlated Electrons DMFT at 25: Infinite Dimensions Forschungszentrum Jülich, September 15, 2014 Supported
More informationElectronic correlations in models and materials. Jan Kuneš
Electronic correlations in models and materials Jan Kuneš Outline Dynamical-mean field theory Implementation (impurity problem) Single-band Hubbard model MnO under pressure moment collapse metal-insulator
More informationMagnetic Moment Collapse drives Mott transition in MnO
Magnetic Moment Collapse drives Mott transition in MnO J. Kuneš Institute of Physics, Uni. Augsburg in collaboration with: V. I. Anisimov, A. V. Lukoyanov, W. E. Pickett, R. T. Scalettar, D. Vollhardt,
More informationMany-body effects in iron pnictides and chalcogenides
Many-body effects in iron pnictides and chalcogenides separability of non-local and dynamical correlation effects Jan M. Tomczak Vienna University of Technology jan.tomczak@tuwien.ac.at Emergent Quantum
More informationThe Gutzwiller Density Functional Theory
The Gutzwiller Density Functional Theory Jörg Bünemann, BTU Cottbus I) Introduction 1. Model for an H 2 -molecule 2. Transition metals and their compounds II) Gutzwiller variational theory 1. Gutzwiller
More informationTheory of magnetic interactions in real materials. Mikhail Katsnelson
Theory of magnetic interactions in real materials Mikhail Katsnelson Outline 1. Introduction 2. Exchange interactions from first principles 3. Beyond DFT: correlated systems and LDA+DMFT 4. Applications:
More informationNew perspectives in superconductors. E. Bascones Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC)
New perspectives in superconductors E. Bascones Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC) E. Bascones leni@icmm.csic.es Outline Talk I: Correlations in iron superconductors Introduction
More informationNiO - hole doping and bandstructure of charge transfer insulator
NiO - hole doping and bandstructure of charge transfer insulator Jan Kuneš Institute for Physics, Uni. Augsburg Collaboration: V. I. Anisimov S. L. Skornyakov A. V. Lukoyanov D. Vollhardt Outline NiO -
More informationFluctuating exchange theory of dynamical electron correlations and magnetism
Fluctuating exchange theory of dynamical electron correlations and magnetism Václav Drchal Institute of Physics ASCR, Praha, Czech Republic Grant Agency of ASCR: project IAA11616 Workshop Frontiers in
More informationSpectral Density Functional Theory
Spectral Density Functional Theory Sergej Savrasov Financial support NSF US DOE LANL Collaborators and Content Constructing New Functionals to Access Energetics and Spectra of Correlated Solids Phonons
More informationRealistic Modeling of Materials with Strongly Correlated Electrons
Realistic Modeling of Materials with Strongly Correlated Electrons G. Keller 1, K. Held 2, V. Eyert 1, V. I. Anisimov 3, K. Byczuk 1, M. Kollar 1, I. Leonov 1, X. Ren 1, and D. Vollhardt 1 1 Theoretical
More informationFerromagnetism and Metal-Insulator Transition in Hubbard Model with Alloy Disorder
Ferromagnetism and Metal-Insulator Transition in Hubbard Model with Alloy Disorder Krzysztof Byczuk Institute of Physics, Augsburg University Institute of Theoretical Physics, Warsaw University October
More informationRole of Hund Coupling in Two-Orbital Systems
Role of Hund Coupling in Two-Orbital Systems Gun Sang Jeon Ewha Womans University 2013-08-30 NCTS Workshop on Quantum Condensation (QC13) collaboration with A. J. Kim, M.Y. Choi (SNU) Mott-Hubbard Transition
More informationAn efficient impurity-solver for the dynamical mean field theory algorithm
Papers in Physics, vol. 9, art. 95 (217) www.papersinphysics.org Received: 31 March 217, Accepted: 6 June 217 Edited by: D. Domínguez Reviewed by: A. Feiguin, Northeastern University, Boston, United States.
More informationCluster Extensions to the Dynamical Mean-Field Theory
Thomas Pruschke Institut für Theoretische Physik Universität Göttingen Cluster Extensions to the Dynamical Mean-Field Theory 1. Why cluster methods? Thomas Pruschke Institut für Theoretische Physik Universität
More informationDiagrammatic Monte Carlo methods for Fermions
Diagrammatic Monte Carlo methods for Fermions Philipp Werner Department of Physics, Columbia University PRL 97, 7645 (26) PRB 74, 15517 (26) PRB 75, 8518 (27) PRB 76, 235123 (27) PRL 99, 12645 (27) PRL
More informationElectronic structure calculations results from LDA+U method
Electronic structure calculations results from LDA+U method Vladimir I. Anisimov Institute of Metal Physics Ekaterinburg, Russia LDA+U method applications Mott insulators Polarons and stripes in cuprates
More informationAn introduction to the dynamical mean-field theory. L. V. Pourovskii
An introduction to the dynamical mean-field theory L. V. Pourovskii Nordita school on Photon-Matter interaction, Stockholm, 06.10.2016 OUTLINE The standard density-functional-theory (DFT) framework An
More informationCollege of Chemistry, Peking University, Beijing, China. Fritz-Haber-Institut der MPG, Berlin, Germany
KITP Program Excitations in Condensed Matter Localized and Itinerant States in a Unified Picture beyond Density Functional Theory Hong Jiang 1, Patrick Rinke 2 and Matthias Scheffler 2 1 College of Chemistry,
More informationDynamical Mean Field Theory and Numerical Renormalization Group at Finite Temperature: Prospects and Challenges
Dynamical Mean Field Theory and Numerical Renormalization Group at Finite Temperature: Prospects and Challenges Frithjof B. Anders Institut für Theoretische Physik Universität Bremen Göttingen, December
More informationTopological Kondo Insulators!
Topological Kondo Insulators! Maxim Dzero, University of Maryland Collaborators: Kai Sun, University of Maryland Victor Galitski, University of Maryland Piers Coleman, Rutgers University Main idea Kondo
More informationDMFT for correlated bosons and boson-fermion mixtures
DMFT for correlated bosons and boson-fermion mixtures Workshop on Recent developments in dynamical mean-field theory ETH ürich, September 29, 2009 Dieter Vollhardt Supported by Deutsche Forschungsgemeinschaft
More informationReview of typical behaviours observed in strongly correlated systems. Charles Simon Laboratoire CRISMAT, CNRS and ENSICAEN, F14050 Caen.
Review of typical behaviours observed in strongly correlated systems Charles Simon Laboratoire CRISMAT, CNRS and ENSICAEN, F14050 Caen. Introduction : Major part of solid state physics of the second part
More informationExamples of Lifshitz topological transition in interacting fermionic systems
Examples of Lifshitz topological transition in interacting fermionic systems Joseph Betouras (Loughborough U. Work in collaboration with: Sergey Slizovskiy (Loughborough, Sam Carr (Karlsruhe/Kent and Jorge
More informationO. Parcollet CEA-Saclay FRANCE
Cluster Dynamical Mean Field Analysis of the Mott transition O. Parcollet CEA-Saclay FRANCE Dynamical Breakup of the Fermi Surface in a doped Mott Insulator M. Civelli, M. Capone, S. S. Kancharla, O.P.,
More informationPreface Introduction to the electron liquid
Table of Preface page xvii 1 Introduction to the electron liquid 1 1.1 A tale of many electrons 1 1.2 Where the electrons roam: physical realizations of the electron liquid 5 1.2.1 Three dimensions 5 1.2.2
More informationLocal moment approach to the multi - orbital single impurity Anderson and Hubbard models
Local moment approach to the multi - orbital single impurity Anderson and Hubbard models Anna Kauch Institute of Theoretical Physics Warsaw University PIPT/Les Houches Summer School on Quantum Magnetism
More informationNano-DMFT : the electronic structure of small, strongly correlated, systems
Nano-DMFT : the electronic structure of small, strongly correlated, systems Nanoscale Dynamical Mean-Field Theory for Molecules and Mesoscopic Devices in the Strong-Correlation Regime Author: S. Florens,
More informationOrigin of the superconducting state in the collapsed tetragonal phase of KFe 2 As 2 : Supplemental Information
Origin of the superconducting state in the collapsed tetragonal phase of KFe As : Supplemental Information Daniel Guterding, Steffen Backes, Harald O. Jeschke, and Roser Valentí Institut für Theoretische
More informationMaterial Science II. d Electron systems
Material Science II. d Electron systems 1. Electronic structure of transition-metal ions (May 23) 2. Crystal structure and band structure (June 13) 3. Mott s (June 20) 4. Metal- transition (June 27) 5.
More informationThe Mott Metal-Insulator Transition
Florian Gebhard The Mott Metal-Insulator Transition Models and Methods With 38 Figures Springer 1. Metal Insulator Transitions 1 1.1 Classification of Metals and Insulators 2 1.1.1 Definition of Metal
More informationTheory of carbon-based magnetism
Theory of carbon-based magnetism Mikhail Katsnelson Theory of Condensed Matter Institute for Molecules and Materials RU Outline sp magnetism in general: why it is interesting? Defect-induced magnetism
More informationThe Hubbard model out of equilibrium - Insights from DMFT -
The Hubbard model out of equilibrium - Insights from DMFT - t U Philipp Werner University of Fribourg, Switzerland KITP, October 212 The Hubbard model out of equilibrium - Insights from DMFT - In collaboration
More informationSpin correlations in conducting and superconducting materials Collin Broholm Johns Hopkins University
Spin correlations in conducting and superconducting materials Collin Broholm Johns Hopkins University Supported by U.S. DoE Basic Energy Sciences, Materials Sciences & Engineering DE-FG02-08ER46544 Overview
More informationLOCAL MOMENTS NEAR THE METAL-INSULATOR TRANSITION
LOCAL MOMENTS NEAR THE METAL-INSULATOR TRANSITION Subir Sachdev Center for Theoretical Physics, P.O. Box 6666 Yale University, New Haven, CT 06511 This paper reviews recent progress in understanding the
More informationMagnetic Oxides. Gerald F. Dionne. Department of Materials Science and Engineering Massachusetts Institute of Technology
Magnetic Oxides Gerald F. Dionne Department of Materials Science and Engineering Massachusetts Institute of Technology Spins in Solids Summer School University of Virginia Charlottesville, VA 21 June 2006
More informationCondensed matter theory Lecture notes and problem sets 2012/2013
Condensed matter theory Lecture notes and problem sets 2012/2013 Dmitri Ivanov Recommended books and lecture notes: [AM] N. W. Ashcroft and N. D. Mermin, Solid State Physics. [Mar] M. P. Marder, Condensed
More informationStrongly Correlated Materials: Insights From Dynamical Mean-Field Theory
Strongly Correlated Materials: Insights From Dynamical Mean-Field Theory Materials with correlated electrons exhibit some of the most intriguing phenomena in condensed matter physics. A new theoretical
More informationZhiping Yin. Department of Physics, Rutgers University Collaborators: G. Kotliar, K. Haule
DFT+DMFT to Correlated Electronic Structures: Recent Developments and Applications to Iron-based Superconductors Zhiping Yin Department of Physics, Rutgers University Collaborators: G. Kotliar, K. Haule
More informationarxiv: v2 [cond-mat.str-el] 12 May 2015
Magnetic interactions in iron superconductors: A review E. Bascones, B. Valenzuela, and M.J. Calderón Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, Cantoblanco, E-28049 Madrid (Spain). (Dated:
More informationDe l atome au. supraconducteur à haute température critique. O. Parcollet Institut de Physique Théorique CEA-Saclay, France
De l atome au 1 supraconducteur à haute température critique O. Parcollet Institut de Physique Théorique CEA-Saclay, France Quantum liquids Quantum many-body systems, fermions (or bosons), with interactions,
More information1 G. Kotliar: Lecture 2
1 G. Kotliar: Lecture 2 In the previous lecture, following some motivation to study strongly correlated electron systems, we introduced a general methodology for constructing mean field theories. To apply
More informationMore a progress report than a talk
Superconductivity and Magnetism in novel Fe-based superconductors Ilya Eremin 1,2 and Maxim Korshunov 1 1 - Max-Planck Institut für Physik komplexer Systeme, Dresden, 2- Institut für Theoretische Physik,
More informationRole of the Octahedra Rotation on the Electronic Structures of 4d Transition Metal Oxides
Role of the Octahedra Rotation on the Electronic Structures of 4d Transition Metal Oxides Changyoung Kim Dept. Physics, Yonsei University B. J. Kim 1, J. Yu 1, S. J. Oh 1, H. Koh 2, I. Nagai 3, S. I. Ikeda
More informationSurface effects in frustrated magnetic materials: phase transition and spin resistivity
Surface effects in frustrated magnetic materials: phase transition and spin resistivity H T Diep (lptm, ucp) in collaboration with Yann Magnin, V. T. Ngo, K. Akabli Plan: I. Introduction II. Surface spin-waves,
More informationIntermediate valence in Yb Intermetallic compounds
Intermediate valence in Yb Intermetallic compounds Jon Lawrence University of California, Irvine This talk concerns rare earth intermediate valence (IV) metals, with a primary focus on certain Yb-based
More informationElectron Correlation
Series in Modern Condensed Matter Physics Vol. 5 Lecture Notes an Electron Correlation and Magnetism Patrik Fazekas Research Institute for Solid State Physics & Optics, Budapest lb World Scientific h Singapore
More informationAll-Electron Full-Potential Calculations at O(ASA) Speed A Fata Morgana?
All-Electron Full-Potential Calculations at O(ASA) Speed A Fata Morgana? SFB 484, Teilprojekt D6 October 5, 2007 Outline 1 2 3 Outline 1 2 3 Outline 1 2 3 Outline 1 2 3 Back in the 1930 s... John C. Slater
More informationSuperconductivity in Fe-based ladder compound BaFe 2 S 3
02/24/16 QMS2016 @ Incheon Superconductivity in Fe-based ladder compound BaFe 2 S 3 Tohoku University Kenya OHGUSHI Outline Introduction Fe-based ladder material BaFe 2 S 3 Basic physical properties High-pressure
More informationStrong Correlation Effects in Fullerene Molecules and Solids
Strong Correlation Effects in Fullerene Molecules and Solids Fei Lin Physics Department, Virginia Tech, Blacksburg, VA 2461 Fei Lin (Virginia Tech) Correlations in Fullerene SESAPS 211, Roanoke, VA 1 /
More informationNumerical Methods in Quantum Many-body Theory. Gun Sang Jeon Pyeong-chang Summer Institute 2014
Numerical Methods in Quantum Many-body Theory Gun Sang Jeon 2014-08-25 Pyeong-chang Summer Institute 2014 Contents Introduction to Computational Physics Monte Carlo Methods: Basics and Applications Numerical
More informationIMPACT ionization and thermalization in photo-doped Mott insulators
IMPACT ionization and thermalization in photo-doped Mott insulators Philipp Werner (Fribourg) in collaboration with Martin Eckstein (Hamburg) Karsten Held (Vienna) Cargese, September 16 Motivation Photo-doping:
More informationSECOND PUBLIC EXAMINATION. Honour School of Physics Part C: 4 Year Course. Honour School of Physics and Philosophy Part C C3: CONDENSED MATTER PHYSICS
A11046W1 SECOND PUBLIC EXAMINATION Honour School of Physics Part C: 4 Year Course Honour School of Physics and Philosophy Part C C3: CONDENSED MATTER PHYSICS TRINITY TERM 2015 Wednesday, 17 June, 2.30
More informationHigh-T c superconductivity in FeSe monolayers: Why T c is so High?
XV Конференция молодых ученых "Проблемы физики твердого тела и высоких давлений Вишневка, пансионат "Буревестник" 16-26 сентября 2016 г. High-T c superconductivity in FeSe monolayers: Why T c is so High?
More informationPHYSICAL REVIEW B 78,
Origin of large thermopower in LiRh O 4 : Calculation of the Seebeck coefficient by the combination of local density approximation and dynamical mean-field theory R. Arita, 1, * K. Kuroki, K. Held, 3 A.
More informationMott physics: from basic concepts to iron superconductors
Mott physics: from basic concepts to iron superconductors E. Bascones Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC) Outline Mott physics: Basic concepts (single orbital & half filling) - Mott
More informationStrongly correlated Cooper pair insulators and superfluids
Strongly correlated Cooper pair insulators and superfluids Predrag Nikolić George Mason University Acknowledgments Collaborators Subir Sachdev Eun-Gook Moon Anton Burkov Arun Paramekanti Affiliations and
More informationTheoretical and experimental study of aromatic hydrocarbon superconductors
Workshop on correlations, criticality, and coherence in quantum systems Theoretical and experimental study of aromatic hydrocarbon superconductors Zhongbing Huang 1 Hubei University, Wuhan, China 2 Beijing
More informationSuperconductivity in Heavy Fermion Systems: Present Understanding and Recent Surprises. Gertrud Zwicknagl
Magnetism, Bad Metals and Superconductivity: Iron Pnictides and Beyond September 11, 2014 Superconductivity in Heavy Fermion Systems: Present Understanding and Recent Surprises Gertrud Zwicknagl Institut
More informationA Twisted Ladder: Relating the Iron Superconductors and the High-Tc Cuprates
A Twisted Ladder: Relating the Iron Superconductors and the High-Tc Cuprates arxiv:0905.1096, To appear in New. J. Phys. Erez Berg 1, Steven A. Kivelson 1, Doug J. Scalapino 2 1 Stanford University, 2
More informationA FERMI SEA OF HEAVY ELECTRONS (A KONDO LATTICE) IS NEVER A FERMI LIQUID
A FERMI SEA OF HEAVY ELECTRONS (A KONDO LATTICE) IS NEVER A FERMI LIQUID ABSTRACT--- I demonstrate a contradiction which arises if we assume that the Fermi surface in a heavy electron metal represents
More informationAnisotropic Magnetic Structures in Iron-Based Superconductors
Anisotropic Magnetic Structures in Iron-Based Superconductors Chi-Cheng Lee, Weiguo Yin & Wei Ku CM-Theory, CMPMSD, Brookhaven National Lab Department of Physics, SUNY Stony Brook Another example of SC
More informationarxiv:cond-mat/ v1 [cond-mat.str-el] 11 Aug 2003
Phase diagram of the frustrated Hubbard model R. Zitzler, N. ong, h. Pruschke, and R. Bulla Center for electronic correlations and magnetism, heoretical Physics III, Institute of Physics, University of
More informationANTIFERROMAGNETIC EXCHANGE AND SPIN-FLUCTUATION PAIRING IN CUPRATES
ANTIFERROMAGNETIC EXCHANGE AND SPIN-FLUCTUATION PAIRING IN CUPRATES N.M.Plakida Joint Institute for Nuclear Research, Dubna, Russia CORPES, Dresden, 26.05.2005 Publications and collaborators: N.M. Plakida,
More informationExcitonic Condensation in Systems of Strongly Correlated Electrons. Jan Kuneš and Pavel Augustinský DFG FOR1346
Excitonic Condensation in Systems of Strongly Correlated Electrons Jan Kuneš and Pavel Augustinský DFG FOR1346 Motivation - unconventional long-range order incommensurate spin spirals complex order parameters
More information1 From Gutzwiller Wave Functions to Dynamical Mean-Field Theory
1 From Gutzwiller Wave Functions to Dynamical Mean-Field Theory Dieter Vollhardt Center for Electronic Correlations and Magnetism University of Augsburg Contents 1 Introduction 2 1.1 Modeling of correlated
More informationThe Oxford Solid State Basics
The Oxford Solid State Basics Steven H. Simon University of Oxford OXFORD UNIVERSITY PRESS Contents 1 About Condensed Matter Physics 1 1.1 What Is Condensed Matter Physics 1 1.2 Why Do We Study Condensed
More informationElectronic structure of correlated electron systems. Lecture 2
Electronic structure of correlated electron systems Lecture 2 Band Structure approach vs atomic Band structure Delocalized Bloch states Fill up states with electrons starting from the lowest energy No
More informationORBITAL SELECTIVITY AND HUND S PHYSICS IN IRON-BASED SC. Laura Fanfarillo
ORBITAL SELECTIVITY AND HUND S PHYSICS IN IRON-BASED SC Laura Fanfarillo FROM FERMI LIQUID TO NON-FERMI LIQUID Strong Correlation Bad Metal High Temperature Fermi Liquid Low Temperature Tuning parameter
More informationORBITAL SELECTIVITY AND HUND S PHYSICS IN IRON-BASED SC. Laura Fanfarillo
ORBITAL SELECTIVITY AND HUND S PHYSICS IN IRON-BASED SC Laura Fanfarillo FROM FERMI LIQUID TO NON-FERMI LIQUID Strong Correlation Bad Metal High Temperature Fermi Liquid Low Temperature Tuning parameter
More informationarxiv:cond-mat/ v1 [cond-mat.str-el] 4 Jul 2000
EPJ manuscript No. (will be inserted by the editor) arxiv:cond-mat/742v1 [cond-mat.str-el] 4 Jul 2 Phase diagram of the three-dimensional Hubbard model at half filling R. Staudt 1, M. Dzierzawa 1, and
More informationw2dynamics : operation and applications
w2dynamics : operation and applications Giorgio Sangiovanni ERC Kick-off Meeting, 2.9.2013 Hackers Nico Parragh (Uni Wü) Markus Wallerberger (TU) Patrik Gunacker (TU) Andreas Hausoel (Uni Wü) A solver
More informationFinite-temperature magnetism in bcc Fe under compression. Xianwei Sha* and R. E. Cohen
Finite-temperature magnetism in bcc Fe under compression Xianwei Sha* and R. E. Cohen Carnegie Institution of Washington, 5251 Broad Branch Road, NW, Washington, D. C. 20015, U. S. A. We investigate the
More informationMagnetic Moment Collapse-Driven Mott Transition in MnO
Magnetic Moment Collapse-Driven Mott Transition in MnO J. Kuneš Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, Augsburg 86135,
More informationAn introduction to Dynamical Mean Field Theory (DMFT) and DFT+DMFT
An introduction to Dynamical Mean Field Theory (DMFT) and DFT+DMFT B. Amadon CEA, DAM, DIF, F-9297 Arpajon, France International summer School in electronic structure Theory: electron correlation in Physics
More informationIntroduction to Density Functional Theory with Applications to Graphene Branislav K. Nikolić
Introduction to Density Functional Theory with Applications to Graphene Branislav K. Nikolić Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, U.S.A. http://wiki.physics.udel.edu/phys824
More informationMagnetism in correlated-electron materials
Magnetism in correlated-electron materials B. Keimer Max-Planck-Institute for Solid State Research focus on delocalized electrons in metals and superconductors localized electrons: Hinkov talk outline
More informationNodal and nodeless superconductivity in Iron-based superconductors
Nodal and nodeless superconductivity in Iron-based superconductors B. Andrei Bernevig Department of Physics Princeton University Minneapolis, 2011 Collaborators: R. Thomale, Yangle Wu (Princeton) J. Hu
More informationarxiv:cond-mat/ v2 [cond-mat.str-el] 16 Feb 2007
An dynamical-mean-field-theory investigation of specific heat and electronic structure of α and δ-plutonium arxiv:cond-mat/0702342v2 [cond-mat.str-el] 16 Feb 2007 L. V. Pourovskii 1, G. Kotliar 2, M. I.
More informationElectronic Structure of Iron Based Superconductors: Pnictides vs. Chalcogenides
Kourovka-34 Electronic Structure of Iron Based Superconductors: Pnictides vs. Chalcogenides M.V.Sadovskii 1,2 In collaboration with E.Z.Kuchinskii 1 and I.A.Nekrasov 1 1 Institute for Electrophysics, Russian
More informationIntroduction to Density Functional Theory
1 Introduction to Density Functional Theory 21 February 2011; V172 P.Ravindran, FME-course on Ab initio Modelling of solar cell Materials 21 February 2011 Introduction to DFT 2 3 4 Ab initio Computational
More informationDynamical mean field approach to correlated lattice systems in and out of equilibrium
Dynamical mean field approach to correlated lattice systems in and out of equilibrium Philipp Werner University of Fribourg, Switzerland Kyoto, December 2013 Overview Dynamical mean field approximation
More informationProbing the Electronic Structure of Complex Systems by State-of-the-Art ARPES Andrea Damascelli
Probing the Electronic Structure of Complex Systems by State-of-the-Art ARPES Andrea Damascelli Department of Physics & Astronomy University of British Columbia Vancouver, B.C. Outline: Part I State-of-the-Art
More informationMott metal-insulator transition on compressible lattices
Mott metal-insulator transition on compressible lattices Markus Garst Universität zu Köln T p in collaboration with : Mario Zacharias (Köln) Lorenz Bartosch (Frankfurt) T c Mott insulator p c T metal pressure
More informationFirst-Principles Calculation of Exchange Interactions
Chapter 2 First-Principles Calculation of Exchange Interactions Before introducing the first-principles methods for the calculation of exchange interactions in magnetic systems we will briefly review two
More informationMetal-insulator transitions
Metal-insulator transitions Bandwidth control versus fillig control Strongly correlated Fermi liquids Spectral weight transfer and mass renormalization Bandwidth control Filling control Chemical potential
More informationMagnetism at finite temperature: molecular field, phase transitions
Magnetism at finite temperature: molecular field, phase transitions -The Heisenberg model in molecular field approximation: ferro, antiferromagnetism. Ordering temperature; thermodynamics - Mean field
More informationLocal moment approach to multi-orbital Anderson and Hubbard models
Local moment approach to multi-orbital Anderson and Hubbard models Anna Kauch 1 and Krzysztof Byczuk,1 1 Institute of Theoretical Physics, Warsaw University, ul. Hoża 69, PL--681 Warszawa, Poland Theoretical
More informationIntroduction to SDFunctional and C-DMFT
Introduction to SDFunctional and C-DMFT A. Lichtenstein University of Hamburg In collaborations with: M. Katsnelson, V. Savkin, L. Chioncel, L. Pourovskii (Nijmegen) A. Poteryaev, S. Biermann, M. Rozenberg,
More informationSOLID STATE PHYSICS. Second Edition. John Wiley & Sons. J. R. Hook H. E. Hall. Department of Physics, University of Manchester
SOLID STATE PHYSICS Second Edition J. R. Hook H. E. Hall Department of Physics, University of Manchester John Wiley & Sons CHICHESTER NEW YORK BRISBANE TORONTO SINGAPORE Contents Flow diagram Inside front
More informationLuigi Paolasini
Luigi Paolasini paolasini@esrf.fr LECTURE 4: MAGNETIC INTERACTIONS - Dipole vs exchange magnetic interactions. - Direct and indirect exchange interactions. - Anisotropic exchange interactions. - Interplay
More informationGreen's Function in. Condensed Matter Physics. Wang Huaiyu. Alpha Science International Ltd. SCIENCE PRESS 2 Beijing \S7 Oxford, U.K.
Green's Function in Condensed Matter Physics Wang Huaiyu SCIENCE PRESS 2 Beijing \S7 Oxford, U.K. Alpha Science International Ltd. CONTENTS Part I Green's Functions in Mathematical Physics Chapter 1 Time-Independent
More informationMikhail Katsnelson. Theory of Condensed Matter Institute for Molecules and Materials RU
Theory of carbon-based based magnetism Mikhail Katsnelson Theory of Condensed Matter Institute for Molecules and Materials RU Outline sp magnetism in general: why it is interesting? Defect-induced magnetism
More informationarxiv:cond-mat/ v1 [cond-mat.str-el] 21 Mar 2006
Non-Fermi-liquid phases in the two-band Hubbard model: Finite-temperature exact diagonalization study of Hund s rule coupling A. Liebsch and T. A. Costi Institut für Festkörperforschung, Forschungszentrum
More informationAbsence of orbital-dependent Mott transition in Ca 2 x Sr x RuO 4
EUROPHYSICS LETTERS 1 July 23 Europhys. Lett., 63 (1), pp. 97 13 (23) Absence of orbital-dependent Mott transition in Ca 2 x Sr x RuO 4 A. Liebsch Institut für Festkörperforschung, Forschungszentrum Jülich
More informationSurprises in Correlated Electron Physics
Vol. 111 (2007) ACTA PHYSICA POLONICA A No. 4 Proceedings of the XII National School Correlated Electron Systems..., Ustroń 2006 Surprises in Correlated Electron Physics K. Byczuk a,b, W. Hofstetter c,
More informationMott insulators. Introduction Cluster-model description Chemical trend Band description Self-energy correction
Mott insulators Introduction Cluster-model description Chemical trend Band description Self-energy correction Introduction Mott insulators Lattice models for transition-metal compounds Hubbard model Anderson-lattice
More information