Description

Layout. Prologue to emphatically associated electrons.Introduction to Dynamical Mean Field Theory (DMFT)First Application. The Mott move issue. Hypothesis and experiments.More reasonable counts. LDA DMFT. Pu Am and the Mott move over the actinide arrangement. Pu and AmCluster Extensions. Application to Cuprate Superconductors. Conclusions. Current advancements and future direc

Transcripts

Prologue to Strongly Correlated Electron Materials and to Dynamical Mean Field Theory (DMFT). Gabriel Kotliar Physics Department and Center for Materials Theory Rutgers University Workshop on Quantum Materials Heron Island Resort New Queensland Australia 1-4 June 2005

Outline Introduction to unequivocally associated electrons. Prologue to Dynamical Mean Field Theory (DMFT) First Application. The Mott move issue. Hypothesis and tests. More sensible computations. LDA +DMFT. Pu Am and the Mott move over the actinide arrangement. Pu and Am Cluster Extensions. Application to Cuprate Superconductors. Conclusions. Current improvements and future bearings.

Electrons in a Solid:the Standard Model Band Theory: electrons as waves. Landau Fermi Liquid Theory. Inflexible groups , optical moves , thermodynamics, transport… … Quantitative Tools. Thickness Functional Theory+Perturbation Theory.

Success story : Density Functional Linear Response Tremendous advancement in stomach muscle initio demonstrating of cross section progression & electron-phonon connections has been accomplished ( Review: Baroni et.al, Rev. Mod. Phys, 73 , 515, 2001 )

The achievement of the standard model does NOT reach out to emphatically related frameworks . Peculiarities can\'t be comprehended inside a RIGID BAND PICTURE,e.g. extremely resistive metals C. Urano et. al. PRL 85, 1052 (2000)

Strong Correlation Anomalies : temperature reliance of the coordinated optical weight up to high recurrence. Infringement of low vitality optical total guideline. Breakdown of unbending band picture.

Breakdown of standard model Large metallic resistivities surpassing as far as possible. Most extreme metallic resistivity 200 m ohm cm Breakdown of the unbending band picture. Strange exchange of phantom weight in photoemission and optics. The quantitative devices of the standard model come up short, e.g. alpha gamma move in Cerium, Mott move in oxides, actinides and so on…

Correlated Materials do huge things Huge resistivity changes V 2 O 3 . Copper Oxides. (La 2-x Ba x ) CuO 4 High Temperature Superconductivity . 150 K in the Ca 2 Ba 2 Cu 3 HgO 8 . Uranium and Cerium Based Compounds. Substantial Fermion Systems,CeCu 6 ,m*/m=1000 (La 1-x Sr x )MnO 3 Colossal Magneto-resistance.

Strongly Correlated Materials. Expansive thermoelectric reaction in NaCo 2-x Cu x O 4 Huge volume breakdown, Ce, Pu… … Large and ultrafast optical nonlinearities Sr 2 CuO 3 Large Coexistence of Ferroelectricity and Ferromagnetism (multiferroics) YMnO3.

Localization versus Delocalization Strong Correlation Problem Many intriguing mixes don\'t fit inside the "Standard Model". Have a tendency to have components with halfway filled d and f shells. Rivalry amongst active and Coulomb collaborations. Breakdown of the wave picture. Need to fuse a genuine space viewpoint (Mott). Non perturbative issue. Require a structure that joins both nuclear material science and band hypothesis. DMFT.

Two ways for the computation of electronic structure of materials Crystal structure +Atomic positions Model Hamiltonian Correlation Functions Total Energies and so on

MODEL HAMILTONIAN AND OBSERVABLES Parameters: U/t , T, transporter focus, dissatisfaction : Local Spectral Function Limiting case nomad electrons Limiting case restricted electrons Hubbard groups

Limit of extensive cross section coordination Metzner Vollhardt, 89 Muller-Hartmann 89

Mean-Field Classical versus Quantum Classical case Quantum case A. Georges, G. Kotliar Phys. Rev. B 45, 6497(1992) Review: G. Kotliar and D. Vollhardt Physics Today 57,(2004)

Mean-Field Quantum Case H=Ho +Hm +Hm0 Determine the parameters of the mediu t\' in order to get interpretation invariance on the normal . A. Georges, G. Kotliar Phys. Rev. B 45, 6497(1992)

DMFT as a guess to the Baym Kadanoff practical

DMFT Cavity Construction. A. Georges and G. Kotliar PRB 45, 6479 (1992). In the first place upbeat marriage of nuclear and band material science. Surveys: A. Georges G. Kotliar W. Krauth and M. Rozenberg RMP68 , 13, 1996 Gabriel Kotliar and Dieter Vollhardt Physics Today 57,(2004)

Pressure Driven Mott move R. Mckenzie, Science 278 , 820-821 (1997). How does the electron go from the confined to as far as possible ?

M. Rozenberg et. al. Phys. Rev. Lett. 75, 105 (1995) T/W Phase chart of a Hubbard model with halfway dissatisfaction at whole number filling. Considering the Mott move in single site DMFT. High temperature comprehensiveness

M. Rozenberg et. al. Phys. Rev. Lett. 75, 105 (1995) T/W Phase graph of a Hubbard model with incomplete disappointment at whole number filling. Contemplating the Mott move in single site DMFT. High temperature comprehensiveness

Evolution of the Spectral Function with Temperature Anomalous exchange of phantom weight associated with the vicinity to the Ising Mott endpoint (Kotliar Lange nd Rozenberg Phys. Rev. Lett. 84, 5180 (2000)

V2O3:Anomalous exchange of phantom weight Th. Pruschke and D. L. Cox and M. Jarrell, Europhysics Lett. , 21 (1993), 593 M. Rozenberg G. Kotliar H. Kajueter G Tahomas D. Rapkikne J Honig and P Metcalf Phys. Rev. Lett. 75, 105 (1995)

Transfer of optical ghostly weight M. Rozenberg G. Kotliar H. Kajueter G Tahomas D. Rapkikne J Honig and P Metcalf Phys. Rev. Lett. 75, 105 (1995)

Anomalous exchange of optical phantom weight, NiSeS. [Miyasaka and Takagi 2000]

Anomalous Resistivity and Mott move Ni Se 2-x S x Crossover from Fermi fluid to awful metal to semiconductor to paramagnetic cover. M. Rozenberg G. Kotliar H. Kajueter G Tahomas D. Rapkikne J Honig and P Metcalf Phys. Rev. Lett. 75, 105 (1995)

demonstrated to triangular grid displayed to triangular cross section t\' t\' k - (ET) 2 X are crosswise over Mott move ET = Insulating anion layer X - 1 directing ET layer [(ET) 2 ] +1

Single site DMFT and kappa organics Merino and McKenzie PRB 61, 7996 (2000)and 62 16442 (2000)

Ising basic endpoint! In V 2 O 3 P. Limelette et.al. Science 302, 89 (2003)

ARPES estimations on NiS 2-x Se x Matsuura et. Al Phys. Rev B 58 (1998) 3690. Doniaach and Watanabe Phys. Rev. B 57, 3829 (1998) Mo et al., Phys. Rev.Lett. 90 , 186403 (2003). .

Conclusions. Three pinnacle structure, quasiparticles and Hubbard groups. Non nearby exchange of unearthly weight. Extensive metallic resistivities. The Mott move is driven by exchange of ghostly weight from low to high vitality as we approach the restricted stage. Lucid and incongruity hybrid. Genuine and energy space. Hypothesis and investigations start to concede to an expansive picture.

Collaborators References Reviews: A. Georges G. Kotliar W. Krauth and M. Rozenberg RMP68 , 13, (1996). Surveys: G. Kotliar S. Savrasov K. Haule V. Oudovenko O. Parcollet and C. Marianetti. Submitted to RMP (2005). Gabriel Kotliar and Dieter Vollhardt Physics Today 57,(2004)

Extensions of Single Site DMFT and its applications to corresponded materials. More reasonable estimations. LDA +DMFT. Pu Am and the Mott move over the actinide arrangement. Bunch Extensions. Application to Cuprate Superconductors. Conclusions. Current advancements and future bearings. Prologue to emphatically related electrons. Prologue to Dynamical Mean Field Theory (DMFT) First Application. The Mott move issue. Hypothesis and examinations.

Two ways for figuring of electronic structure of unequivocally associated materials Crystal structure +Atomic positions Model Hamiltonian Correlation Functions Total Energies and so on. DMFT thoughts can be utilized as a part of both cases.

Dynamical Mean Field Theory Basic thought: diminish the quantum numerous body issue to a one site or a bunch of locales, in a medium of non collaborating electrons complying with a self consistency condition.[A. Georges and GK Phys. Rev. B 45, 6497, 1992]. Combine nuclear material science and band hypothesis. Molecule in a medium. Weiss field. = Quantum debasement model. Strong in a recurrence subordinate potential. Consolidate band structure and orbital decadence to achive a sensible depiction of materials. LDA +DMFT. Sensible blend with band hypothesis: LDA+DMFT V. Anisimov, A. Poteryaev, M. Korotin, A. Anokhin and G. Kotliar, J. Phys. Cond. Mat. 35, 7359 (1997). .

LDA+DMFT V. Anisimov, A. Poteryaev, M. Korotin, A. Anokhin and G. Kotliar, J. Phys. Cond. Mat. 35, 7359 (1997). The light, sp (or spd) electrons are amplified, very much depicted by LDA .The overwhelming, d (or f) electrons are restricted treat by DMFT. Use Khon Sham Hamiltonian in the wake of substracting the normal vitality effectively contained in LDA. Add to the substracted Kohn Sham Hamiltonian a recurrence subordinate self vitality, treat with DMFT. In this strategy U is either a parameter or is evaluated from obliged LDA Describes the excitation spectra of numerous unequivocally associated solids. .

Spectral Density Functional Determine the self vitality , the thickness and the structure of the strong self reliably. By extremizing an utilitarian of these amounts. (Chitra, Kotliar, PRB 2001, Savrasov, Kotliar, PRB 2005). Coupling of electronic degrees of flexibility to basic degrees of opportunity. Full usage for Pu. Savrasov and Kotliar Nature 2001. A work in progress. Useful of G and W, self reliable assurance of the Coulomb communication and the Greens fu

LDA+DMFT Self-Consistency circle Edc U DMFT

Pu in the intermittent table actinides

Mott Transition in the Actinide Series Lashley et.al .

Pu stages