Basic Energy Sciences Basic Energy Sciences Theoretical Condensed Matter Physics Condensed Matter Physics & Materials Chemistry Team Materials Sciences and Engineering Division Overview of Theory and Overview of Theory and Simulation in the Simulation in the Division of Materials Division of Materials Sciences and Engineering Sciences and Engineering Dale D. Koelling Dale D. Koelling Program Manager Program Manager Theoretical Condensed Theoretical Condensed Matter Physics Matter Physics Office of Basic Energy Sciences Office of Basic Energy Sciences Office of Science, U.S. Department of Energy Office of Science, U.S. Department of Energy
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Basic Energy Sciences Theoretical Condensed Matter Physics Condensed Matter Physics & Materials Chemistry Team Materials Sciences and Engineering Division.
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Basic Energy SciencesBasic Energy SciencesTheoretical Condensed Matter Physics
Materials and Engineering Physics: Dispersed Theory
• Structure and Composition of Materials: dynamic behavior of nanostructures; greater ability to treat inhomogeneous materials, esp. disorder; includes the effort on the constrained local moment model for spin dynamics.
• Mechanical Behavior of Materials and Radiation Effects: predict material behavior under exposure conditions (irradiation, temperature, and mechanical loading) that represent a significant extrapolation beyond our existing knowledge base.
• Physical Behavior of Materials: coupling of length scales from atomic to macroscopic; organic electronic materials --- charge and energy transfer, electronic structure calculation, exciton dynamics and transport, spin dynamics.
• Synthesis and Processing Science: fundamental understanding of mechanisms and processes to aid systematic design.
• Engineering Physics: multiplicity of scales; managing the explosion of data; an INCITE award occurred here.
Basic Energy SciencesBasic Energy SciencesTheoretical Condensed Matter Physics
Calculated state of 512 atoms from paramagnetic (high temperature) bcc iron. The variation of magnetic moment is given by the color scheme. Implementation of the fundamental approach requires intensive computing --- the code has won the top prize for computational efficiency --- but also the resolution of further subtle and difficult fundamental theoretical issues.
The Heisenberg model, long used to describe the magnetic behavior of materials, is a model involving experimentally determined parameters. Recently, a fundamental theory has been formulated for which the Heisenberg model could be considered an approximation. Within this theory, the magnitude of the moments can change as they are rotated as illustrated in the figure. In addition to such new effects, the formalism also enables one to calculate and interpret the strengths of interaction. This will lead to further insights how materials arrange themselves to have magnetic moments and, equally important, how they avoid them.
A major step forward towards understanding magnetic materials, this theory is extends Density Functional Theory and utilizes it in regimes where numerous aspects are still not well understood. Consequently, applying this theory will simultaneously enhance our understanding of magnetic materials and of the basic theory. It is also a non-trivial computational effort! ◄
Dynamics of SpinsDynamics of Spins
Basic Energy SciencesBasic Energy SciencesTheoretical Condensed Matter Physics
• The projects were selected under a new competitive program, entitled Innovative and Novel Computational Impact on Theory and Experiment (INCITE), announced last July by Energy Secretary Spencer Abraham.
• 52 proposals were submitted.
• Three awards amount to 10 percent of the total computing time available this year on NERSC's current IBM SP3.
• “Fluid Turbulence and Mixing at High Reynolds Number," led by P.K. Yeung (Georgia Tech.), was awarded 1,200,000 processor hours in the area of forced isotropic turbulence. The principal investigators have NSF grants but their INCITE activities are a part of the Engineering Physics activity.
Basic Energy SciencesBasic Energy SciencesTheoretical Condensed Matter Physics
• Theory is primarily concentrated in the Theoretical Condensed Matter Physics activity --- although it is not exclusively so. : Multiple length and time scales; Complex systems; Many body effects; Predictive; Multidisciplinary Efforts!!! (CMSN & 03-17 Solicitation) ◄▪▪▪▪▪▪
• Materials Chemistry: treatments of nanostructured 2 & 3 dimensional materials with chemical accuracy; interactions and transport phenomena at interfaces; novel multiscale approaches for large complex systems that link spatial and temporal scales.
• While concepts are emphasized here, we are effectively using a lot of computing and can really benefit from further development!
Basic Energy SciencesBasic Energy SciencesTheoretical Condensed Matter Physics
The mission of the Computational Materials Science Network is to advance frontiers in computational materials science by assembling diverse sets of researchers committed to working together to solve relevant materials problems that require cooperation across organizational and disciplinary boundaries.
[http://www.phys.washington.edu/~cmsn]
Basic Energy SciencesBasic Energy SciencesTheoretical Condensed Matter Physics
• focus on critical scientific issue {operationally modified}• have a clear path to relevance (i.e., real materials issues) • be of the type best pursued through broad cooperative efforts, as
opposed to those key problems best tackled by single investigator groups
• build on existing BES funded programs • define some short-term deliverables combined with long-term
objectives • a strong synergism with experimental and industrial programs is
highly encouraged
And so shall ye be judged!
Basic Energy SciencesBasic Energy SciencesTheoretical Condensed Matter Physics
• Last year, over 3.35x106 processor hours were used on the IBM SP3 at the National Energy Research Supercomputer Center and ~1.6x106 IBM SP3 & SP4 processor hours helping evaluate computers at Oak Ridge National Laboratory. (The two machines involved will become a part of the production system this year.)
• At 45 repositories (account for PI and coworkers), MATSCI is the program with the largest “population” of users.
• Requests for time ran roughly 3 times the resources available this year BEFORE NEW, LARGE SPECIAL REQUESTS.