Wei Ku

Condensed Matter Physics & Materials Science Department, Brookhaven National Laboratory, Bldg 510
Upton, NY 11973-5000 (631) 344-2684

weiku@bnl.gov / weiku@mailaps.org http://www.cmth.bnl.gov/~weiku/

Education 1995-2000	University of Tennessee Knoxville, TN Ph.D. Physics -- Thesis “Electronic Excitations in Metals and Semiconductors: Ab Initio Studies of Realistic Many-Particle Systems”
1994-1995	Georgia State University Atlanta, GA 15 credit-hours of course work
1987-1991	Tamkang University Tamsui, Taiwan ROC B.S. Physics

Honors

Lawrence Fellowship in Lawrence Livermore National Lab (2003) (fellowship declined) Joe Fowler & Jerry Marion Outstanding Graduate Student Award in Department of Physics, University of Tennessee, Knoxville, USA (1998) Department Head's Award in Department of Physics, TamKang Universy, Tamsui, Taiwan ROC (1988)

Activities

American Physical Society (1999-Present) Vice president of Chinese Student Association at the University of Tennessee, Knoxville (1997) UT/ORNL Collaborative Scientist Program (1996-2000)

Skills

All-electron based first-principles many-body theory of condensed matter systems Quantum magnetism of strongly correlated systems, based on ab initio Wannier function analysis Dynamical charge/magnetic response within time-dependent density functional theory Quasi-particle excitation spectrum within finite temperature many-body perturbation theory Quantum Monte Carlo method Parallel scientific computing (MPI, and OpenMP) Object-oriented numerical methods Computer programming: C++, C, FORTRAN, BASIC, and assembly Platform operation: IBM SP, PC Cluster (with DOS, Windows, or LINUX), Sun Sparc, DEC Alpha, IBM RS6000, and Cray T3E

Relevant Experience 2005-present	Brookhaven National Laboratory Upton, NY Associate Physicist
2003-present	Stony Brook University Stony Brook, NY Adjunct Professor
2003-2005	Brookhaven National Laboratory Upton, NY Associate Physicist
	First-principles derivation of effective reduced Hamiltonian via numerical CD renormalization group methods Bi-orthogonal interpolating wavelet based O(N) energy minimization approach to density functional theory Missing Fermi pockets and Fermi-topology of NaxCoO2 Thermal fluctuation of phase of superconducting order parameter Microscopic electron and phonon mechanisms of charge density wave and charge order Material dependence of high-Tc cuprates Microscopic mechanisms of orbital/charge order of manganites Gapless charge density wave in transition metal dichalcogenides Local excitations of Mott insulators and charge transfer insulators Hybridization and propagation of local Frenkel excitons
2001-2003	University of California Davis, CA Post-graduate Researcher
	Multi-energy-resolution construction of all-electron Wannier functions of highly correlated systems Microscopic analysis of magnetic structure of spin-Peierls CuGeO3, spin-spiral CuSiO3, and ferromagnetic Li2CuO2 chains Dynamical density response of transition metals and oxides (LDA+U) Pressure dependence of ferromagnetism of semiconducting EuO, EuS, EuSe, and EuT Insulating ferromagnetism in half-filled La4Ba2Cu2O10 Microscopic origin of complex magnetic structure of CaCu3Ti4O12 Ab initio construction of 2^nd-quantized lattice Hamiltonian using all-electron Wannier functions Construction of energy-resolved all-electron Wannier function 2D Hubbard model (Quantum Monte Carlo) study of stripes in doped High-Tc superconductors Collective charge excitations in MgB2
1997-2000	University of Tennessee Knoxville, TN and Solid State Division, ORNL Oak Ridge, TN Graduate Research Assistant
	Thesis “Electronic Excitations in Metals and Semiconductors: Ab Initio Studies of Realistic Many-Particle Systems”: first-principles study of electronic excitations in realistic condensed matter within two theoretical frameworks: time-dependent density functional theory (TDDFT), for study of linear density response, and finite-temperature many-body perturbation theory (MBPT) with Kadanoff-Baym conserving (self-consistent) scheme, for study of quasi-particle excitation. Systems studied include simple metals, transition metals and semiconductors. Quasi-particle excitation spectrum of proto-type semiconductors, Si and Ge Many-body self-consistency effect on quasi-particle bandwidth of Na Pure Matsubara time, all-electron, self-consistent GW implementation of finite-temperature many-body perturbation theory d-threshold charge response of Zn and Cd Absence of Landau damping in Cs Anomalous plasmon lifetime dispersion of K All-electron, LAPW implementation of TDDFT linear density response Proposal, design, construction, and configuration of Linux PC cluster “Hive” in the Solid State Division for parallel computing.
1995-1996	University of Tennessee Knoxville, TN Graduate Teaching Assistant
	Undergraduate Lab teaching
1994-1995	Georgia State University Atlanta, GA Graduate Teaching Assistant
	Undergraduate Lab teaching
1993-1994	Tamkang University Tamsui, Taiwan, ROC Coordinator of General Physics Lab.
	Equipment setup and maintenance for General Physics Lab Experiment design and improvement Graduate teaching assistants training and qualifying

Representative Publications	· “Dynamical reconstruction of the exciton in LiF with inelastic x-ray scattering” Peter Abbamonte, Tim Graber, James P. Reed, Serban Smadici, Chen-Lin Yeh, Abhay Shukla, Jean-Pascal Rueff, and Wei Ku, submitted to PNAS (2008) · “Hybridization of local Frenkel excitons in strongly correlated NiO: a first-principles Wannier function approach” Chi-Cheng Lee, Hung-Chung Lee, and Wei Ku, in preparation · “Charge Ordering in Half-Doped Manganites: Weak Charge Disproportion and Leading Mechanisms” D. Volja, W.-G. Yin, and Wei Ku, submitted to Phys. Rev. Lett. (2007) · “Tuning Hole Mobility, Concentration, and Repulsion in High-Tc Cuprates via Apical Atoms” W.-G. Yin and Wei Ku, submitted to Phys. Rev. Lett. (2007) · “Nanoscale Disorder in CaCu3Ti4O12: A New Route to the Enhanced Dielectric Response” Y. Zhu, J. C. Zheng, L. Wu, A. I. Frenkel, J. Hanson, P. Northrup, and W. Ku, Phys. Rev. Lett. 99, 037602 (2007) · “Non-resonant Inelastic X-Ray Scattering and Energy-Resolved Wannier Function Investigation of d-d Excitations in NiO and CoO” B. C. Larson, Wei Ku, J. Z. Tischler, Chi-Cheng Lee, O. D. Restrepo, A. G. Eguiluz, P. Zschack, and K. D. Finkelstein, Phys. Rev. Lett. 99, 026401 (2007) · “Low-Energy Charge-Density Excitations in MgB2: Striking Interplay between Single-Particle and Collective Behavior for Large Momenta” Y. Q. Cai et al., Phys. Rev. Lett. 97, 176402 (2006) · “Orbital ordering in LaMnO3: Electron-lattice versus electron-electron interactions” W.-G. Yin, D. Volja, and Wei Ku, Phys. Rev. Lett. 96, 116405 (2006) · “Coexistence of gapless excitations and commensurate charge-density wave in the 2H-transition metal dichalcogenides” R. L. Barnett, A. P., E. Demler, W.-G. Yin, and Wei Ku, Phys. Rev. Lett. 96, 026406 (2006) · “d-d Excitations in Manganites Probed by Resonant Inelastic X-Ray Scattering” S. Grenier, J. P. Hill, Wei Ku, V. Kiryukhin, V. Oudovenko, Y.-J. Kim, K. J. Thomas, S.-W. Cheong, Y. Tokura, Y. Tomioka, D. Casa, and T. Gog, Phys. Rev. Lett. 94, 047203 (2005) · “Insulating Ferromagnetism in La4Ba2Cu2O10: an Ab Initio Wannier Function Analysis” Wei Ku, H. Rosner, W. E. Pickett, and R. T. Scalettar, Phys. Rev. Lett. 89, 167204 (2002) · “Band-Gap Problem in Semiconductors Revisited: Effects of Core States and Many-Body Self-Consistency” Wei Ku and A. G. Eguiluz, Phys. Rev. Lett. 89, 126401 (2002) · “Ab Initio Investigation of Collective Charge Excitations in MgB2” Wei Ku, W. E. Pickett, R. T. Scalettar, and A. G. Eguiluz, Phys. Rev. Lett. 88, 057001 (2002) · “Electronic Excitations in Metals and Semiconductors: Ab Initio Studies of Realistic Many-Particle Systems” Wei Ku, thesis, University of Tennessee, Knoxville (2000) · “Comment on 'Why is the bandwidth of sodium observed to be narrower in photoemission experiments?' ” Wei Ku, A. G. Eguiluz, and W. E. Plummer, Phys. Rev. Lett. 85, 2410 (2000) · “Plasmon Lifetime in K: A Case Study of Correlated Electrons in Solids Amenable to Ab Initio Theory” Wei Ku and A. G. Eguiluz, Phys. Rev. Lett. 82, 2350 (1999) · “Crucial Role of the Crystal Potential in Magnetism of Edge-Sharing Cu-O Chains and its Interplay with the Bond Angle” H. Rosner, Wei Ku, R. T. Scalettar, W. E. Pickett, S.-L. Drechsler, J. Malek, R. Neudert, M. Knupfer, J. Fink, and H. Eschrig, unpublished
Other Publications	· “A Novel First-Principles Approach to Effective Hamiltonians for high-Tc superconducting cuprates” Wei-Guo Yin and Wei Ku, submitted to JPCS (conference proceedings of LEHTSC2007). · “Synthesis of Ultrathin Palladium and Platinum Nanowires and a Study of Their Magnetic Properties” Xiaowei Teng, Wei-Qiang Han, Wei Ku, Markus Hücker, Angewandte Chemie International Edition, 47, 2055 (2008). · “Effect of Number of Walls on Plasmon Behavior in Carbon Nanotubes” M. H. Upton, R. F. Klie, J. P. Hill, T. Gog, D. Casa, W. Ku, Y. Zhu, M. Y. Sfeir, J. Misewich, G. Eres, D. Lowndes, submitted to Phys. Rev. B (2006) · “Universal quasiparticle decoherence in hole- and electron-doped high-Tc cuprates” Z.-H. Pan, P. Richard, A.V. Fedorov, T. Kondo, T. Takeuchi, S.L. Li, Pengcheng Dai, G.D. Gu, W. Ku, Z. Wang, and H. Ding, submitted to Phys. Rev. Lett. (2006) · “Nature of oxygen dopant-induced states in high-temperature Bi2Sr2CaCu2O8+x superconductors: A photoemission investigation” P. Richard, Z.-H. Pan, M. Neupane, A. V. Fedorov, T. Valla, P. D. Johnson, G. D. Gu, W. Ku, Z. Wang, and H. Ding, Phys. Rev. B 74, 094512 (2006) · “Unusual photoemission resonances of oxygen-dopant induced states in Bi2Sr2CaCu2O8+d” P. Richard, Z.-H. Pan, M. Neupane, A. V. Fedorov, T. Valla, P. D. Johnson, G. D. Gu, W. Ku, Z. Wang, and H. Ding, (preprint) · “Electron-hole and plasmon excitations in 3d transition metals: Ab initio calculations and inelastic x-ray scattering measurements” I. G. Gurtubay, J. M. Pitarke, Wei Ku, A. G. Eguiluz, B. C. Larson, J. Tischler, P. Zschack, and K. D. Finkelstein, Phys. Rev. B 72, 125117 (2005) · “Exchange Coupling in Eu Monochalcogenides from First Principles” J. Kunes, Wei Ku, and W. E. Pickett, J. Phy. Soc. Jap., 74, 1408 (2005) · “Comment on "Band-Gap problem in semiconductors revisited: Effects of core states and many-body self-consistency" – Reply” Wei Ku, A. G. Eguiluz, Phys. Lett. 93, 249702 (2004) · “Large crystal local-field effects in the dynamical structure factor of rutile TiO2” I. G. Gurtubay, Wei Ku, J. M. Pitarke, A. G. Eguiluz, B. C. Larson, J. Tischler, and P. Zschack, Phys. Rev. B 70, 201201 (2004) · “Effects of the crystal structure in the dynamical electron-density response of hcp transition metals” I. G. Gurtubay, Wei Ku, J. M. Pitarke,and A. G. Eguiluz Computational Materials Science 30, 104 (2004) Selected papers of the Twelfth International Workshop on Computational Materials Science (CMS2002) · “Microscopic analysis of Insulating Magnetism of La4Ba4Cu2O10 and Nd4Ba4Cu2O10” Wei Ku, H. Rosner, W. E. Pickett, and R. T. Scalettar, J. Solid State Chem. 171, 329 (2003) · “Self-interaction correction and contact hyperfine field” P. Novák, J. Kune, W. E. Pickett, Wei Ku, and F. R. Wagner, Phys. Rev. B 67, 140403 (2003) · “PAR-dependent and geometry-dependent mechanisms of spindle positioning” M.-F. B. Tsou, Wei Ku, A. Hayashi, and L. S. Rose, J. Cell Bio. 160, 845 (2003) · “MgB2: Complex Behavior from a Simple Compound” H. Rosner, J.M. An, W. Ku, M.D. Johannes, R.T. Scalettar, W.E. Pickett, S.V. Schulga, S.-L. Drechsler, H. Eschrig, W. Weber, and A.G. Eguiluz, Studies of High Temperature Superconductors, Vol. 38, edited by A. Narlikar (Nova, New York, 2001) · “Dynamical Response of Correlated Electrons in Solids Probed by Inelastic Scattering Experiments: An Ab Initio Theoretical Perspective” A. G. Eguiluz, Wei Ku and J. M. Sullivan, J. Phys. Chem. Solids 61, 383 (2000) · “Ab Initio Studies of Electronic Excitations in Real Solids” Adolfo G. Eguiluz and Wei Ku, Electron Correlations and Materials Properties, edited by A. Gonis, N. Kioussis, and M. Ciftan (Kluwer Academic, New York, 1999), p. 329 · “Anomalous Loss Functions of Zn and Cd: Dynamical d-Threshold and Coherent Electron-Hole Response” Wei Ku, and Adolfo G. Eguiluz, unpublished
Invited Presentations	· “Tuning in-plane behavior of high-Tc cuprates via apical atoms: New theoretical findings on the material dependence” Sanibel Symposium (St. Simons Island, Georgia, February 2008) · “Utilizing the short wavelength of X0-ray to study low-energy local excitations: q-dependence of the spectral weights and dispersions” Workshop on “Inelastic X-ray Scattering at NSLS-II” (NSLS-II, January 2008) · “Recent First-Principles Studies of Strongly Correlated Systems: Gapless CDW, orbital/charge ordering and superconducting pair suppression” International workshop on “Novel Methods for Electronic Structure Calculations” (La Plata, Argentina, November 2007) · “Tuning in-plane behavior of high-Tc cuprates via apical atoms: New theoretical findings on the material dependence” LEHTSC2007 “International Symposium on Lattice Effects in Cuprate High Temperature Superconductors – Spin, phonon or third way?” (Tsukuba, Japan, October 2007) · “Recent First-Principles Studies of Strongly Correlated Systems: Gapless CDW, orbital/charge ordering and superconducting pair suppression” Physics Department, University of California, Davis (Davis, September 2007) · “Local excitations in strongly correlated multi-orbital systems: effective kinetic effects in one-and two-particle channels” CMSN workshop (Davis, September 2007) · “Recent First-Principles Studies of Strongly Correlated Systems: Gapless CDW, orbital/charge ordering and superconducting pair suppression” “Wannier functions: what you can do with it and how” Max-Planck Institute for Chemical Physics of Solids (Dresden, July 2007) · “Finite-temperature many-body perturbation theory and conserving scheme” “Wannier functions: what you can do with it and how” Department of Materials Physics, University of Leoben (Leoben, July 2007) · “Recent First-Principles Studies of Strongly Correlated Systems: Gapless CDW, orbital/charge ordering and superconducting pair suppression” Department of Magnetism and Superconductivity Institute of Physics (Prague, July 2007) · “Recent First-Principles Studies of Strongly Correlated Systems: Gapless CDW, orbital/charge ordering and superconducting pair suppression” Department of Physics, University of Nurnberg-Erlangen (Erlangen, July 2007) · “Recent First-Principles Studies of Strongly Correlated Systems: Gapless CDW, orbital/charge ordering and superconducting pair suppression” Center for Electronic Correlations and Magnetism Theoretical Physics III, University of Augsburg (Augsburg, June 2007) · “Symmetry Respecting Wannier Functions and Their Applications in Strongly Correlated Systems: New Development of First-Principles Many-Body Down-Folding Approach” CECAM workshop “Maximally Localized Wannier Functions:Concepts, Applications, and Beyond” (Lyon, June 2007) · “Recent First-Principles Studies of Strongly Correlated Systems: Gapless CDW, orbital/charge ordering and superconducting pair suppression” CNRS - Institut Néel (Grenoble, June 2007) · “Tuning Hold Mobility, Concentration, and Repulsion in High-Tc Cuprates via Apical Atoms: new theoretical findings on the material dependence” DFLFS3 (Port Jefferson, May 2007) · “Tuning Hold Mobility, Concentration, and Repulsion in High-Tc Cuprates via Apical Atoms” CMSN workshop (Denvor, March 2007) · “Recent First-Principles Studies of Strongly Correlated Systems: Gapless CDW, orbital/charge ordering and others” LLNL international workshop on “Correlated Electrons in Matter” (Half Moon Bay, December 2006) · “Recent First-Principles Studies of Strongly Correlated Systems: Gapless CDW, orbital/charge ordering and others” NRL (Washington DC, November 2006) · “Recent First-Principles Studies of Strongly Correlated Systems: Material dependence of high-Tc cuprates” Academia Sinica (Taipei, June 2006) · “Recent first-principles studies of strongly correlated systems: gapless CDW, orbital ordering and others” Department of Physics, TKU (Tamsui, June 2006) · “Bridging first-principles methods and many-body models” OPCA5 (Taipei, Taiwan, Jun 2006) · “First-Principles Many-Body Theories of Excitation and Strongly Correlated Systems” special summer school, NCKU (Tainan, ROC, Jun 2006) · “Filling the missing pieces of the puzzles in strongly correlated systems” Department of Physics, UIUC (Urbana, June 2006) · “Probing local excitations with angular dependence of large-q non-resonant IXS: Sensitivity to weak electronic symmetry breaking in NiO and CoO” APS user meeting, ANL (Chicago, May 2006) · “Recent development of Wannier function and its applications to electronic excitations in strongly correlated systems” workshop on “First-principles approaches to optical and photoelectron spectra” (Munich, March 2006) (declined due to US visa related issues) · “First-Principles Study of Strongly Correlated Systems: filling the missing pieces of the puzzles” Department of Physics, Boston College (Boston, November, 2005) · “Applications of Wannier Functions and Derivation of Effective Hamiltonian of Strongly Correlated Systems” CMSN workshop (Chicago, September 2005) · “First-Principles Study of Strongly Correlated Systems: filling the missing pieces of the puzzles” Department of Physics, Pennsylvania State University (November, 2005) · “First-Principles Study of Strongly Correlated Systems: filling the missing pieces of the puzzles” Department of Physics, Harvard University (Boston, June, 2005) · “First-Principles Study of Strongly Correlated Systems: filling the missing pieces of the puzzles” Department of Physics, Columbia University (New York, April, 2005) · “First-Principles Study of Strongly Correlated Systems: filling the missing pieces of the puzzles” Department of Physics, University of California at Irvine (Irvine, February, 2005) · “Energy-Resolved Wannier States with Assigned Local Symmetry : Recent Development & Applications” CMSN workshop, (Oak Ridge, September 2004) · “Textbook Perturbation Theory at Work in Real Semiconductors: What's all the recent arguments on GW calculations about?” Department of Physics, Rutgers University (Piscataway, April 2003) · “First-Principles Methods of Quasi-Particle and Electron-Hole Excitations” International Workshop on Computational Materials Physics (Taipei, Taiwan, November 2003) · “Magnetic Coupling in Insulating Quasi-1D Cu-O Spin Chains: Toward Fully First-Principles Approaches for Strong Correlation” Workshop on Advanced Material Science (Tamsui, Taiwan, November 2003) · “First-Principles Methods of Quasi-Particle and Electron-Hole Excitations” Department of Physics, Tamkang University (Tamsui, Taiwan, November 2003) · “Magnetic Coupling in Insulating Quasi-1D Cu-O Spin Chains: Toward Fully First-Principles Approaches for Strong Correlation” National Center of Theoretical Sciences (Hsinchu, Taiwan, November 2003) · “Magnetic Coupling in Insulating Quasi-1D Cu-O Spin Chains: Toward Fully First-Principles Approaches for Strong Correlation” Department of Physics, National Sun Yat-Sen University (Kaohsiung, Taiwan, November 2003) · “Simple Construction of Energy-Resolved Wannier States with Assigned Local Symmetry” CMSN workshop (Knoxville, November 2003) · “Magnetic Coupling in Insulating Quasi-1D Cu-O Spin Chains: Toward Fully First-Principles Approaches for Strong Correlation” Department of Physics, SUNY Stony Brook (Stony Brook, October 2003) · “Quasi-Particle Excitation in Semiconductors: All-Electron Conserving GW scheme” ES2003 - Fifteenth Annual Workshop on Recent Developments in Electronic Structure Methods (Minneapolis, May 2003) · “New Understanding and Surprises from Novel Realistic Many-Body Methods: Quasi-Particle Spectrum of Semiconductors and Insulating Ferromagnetism in Cuprates” Lawrence Berkeley National Lab (April, 2003) · “Wannier Function Study of Insulating Ferromagnetism” APS March Meeting (Austin, March 2003) · “Dynamical Electronic Excitations in Real Materials: Perspective of First-Principles Many-Body Theories” McGill University (Montreal, February 2003) · “Dynamical Electronic Excitations in Real Materials: Perspective of First-Principles Many-Body Theories” Lawrence Livermore National Laboratory (Livermore, February 2003) · “Dynamical Electronic Excitations in Real Materials: Perspective of First-Principles Many-Body Theories” Brookhaven National Lab (Upton, November 2002) · “Wannier State Analysis of Insulating Ferromagnetism in La4Ba2Cu2O10” ESCM - Electronic Structure and Computational Magnetism (Washington DC, July 2002) · “Wannier State Analysis of Insulating Ferromagnetism in La4Ba2Cu2O10” Department of Physics, USC (LA, June 2002) · “Microscopic Analysis of Non-Metallic Ferromagnetism in La4Ba2Cu2O10 Based on Ab Initio Wannier Functions” Department of Physics, UC Davis (Davis, March 2002) · “Electronic Excitations in Metals and Semiconductors: Ab Initio Studies of Realistic Many-Body systems”