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Leadership Team The Gang of Four

Tim Germann

Tim Germann

Center Director

Timothy C. Germann is in the Physics and Chemistry of Materials Group (T-1) at Los Alamos National Laboratory (LANL). Tim earned dual Bachelor of Science degrees in Computer Science and in Chemistry from the University of Illinois at Urbana-Champaign in 1991, and a Ph.D. in Chemical Physics from Harvard University in 1995, where he was a DOE Computational Science Graduate Fellow. He is the Director of the DOE/ASCR Exascale Co-Design Center for Materials in Extreme Environments (ExMatEx)” and led the high strain-rate team in the DOE/BES Center for Materials in Mechanical and Irradiation Extremes (CMIME)” an Energy Frontier Research Center (EFRC). Tim has co-authored over 160 peer-reviewed scientific publications with more than 3000 citations, and is 2013-4 Chair of the American Physical Society (APS) Division of Computational Physics.

Jim Belak

Jim Belak

Deputy Director

Jim Belak is a senior scientist in the Condensed Matter and Materials Division at Lawrence Livermore National Laboratory. He is Deputy Director and Co-PI for the Exascale Co-design Center for Materials in Extreme Environments (ExMatEx), a joint project with LANL, LLNL, ORNL, SNL-A, Stanford and CalTech, funded by the DOE Office of Advanced Scientific Computing Research. The goal of ExMatEx is to use the supercomputer codes used to study materials in extreme environments to guide the design of future supercomputers and use the understanding gained to refactor and create new supercomputer codes for materials behavior. He earned his PhD in Condensed Matter Physics from Colorado State University.


David Richards

Algorithms and Applications Lead

David Richards is a computational physicist in the Physical and Life Sciences Directorate at Lawrence Livermore National Laboratory. David received a B.S. in Physics from Harvey Mudd College in 1992 and a Ph.D. In Physics from the University of Illinois at Urbana-Champaign in 1999. He has over 15 years of experience in scientific computing as both a user and application developer in academic, industrial, and national lab settings. In addition to his work on ExMatEx, he also leads a team that is working with scientists at IBM to develop advanced cardiac modeling techniques. In 2007 he was a member of team that won the IEEE/ACM Gordon Bell Award and was named a finalist for that award in 2009 and 2012. His research interests include large scale parallel scientific computing and atomic scale simulation of materials.

Allen McPherson

Allen McPherson

Computer Science Lead

Al is a staff member in the Applied Computer Science group at Los Alamos National Laboratory and leads the Co-Design and Advanced Architectures team. His technical interests include programming models, runtime systems, scientific visualization, and cloud computing. In addition to his role as ExMatEx computer science lead, Al is is Co-PI of the Los Alamos LDRD CoCoMANS co-design project and leads the ASC co-design with proxy apps project. During the summer months, Al also leads the Los Alamos Co-Design Summer School. Before coming to Los Alamos, Al spent 11 years in industry at The Boeing Company in Seattle, Washington. Being the only member of the G4 without a PhD (BA Computer Science, Southern Illinois University, 1978; MS Computer Science, University of New Mexico, 1995) Al is often assigned menial tasks, such as building and maintaining this web site.

Team Members Project staff from national laboratories

Kipton Barros, Los Alamos

Scale-Bridging Algorithms

Nathan Barton, Livermore

High Strain-Rate Applications

Milo Dorr, Livermore

Scale-Bridging Application Lead

Scott Futral, Livermore

Computer Science Co-Lead

Simon Hammond, Sandia

SST Performance Simulation

Christoph Junghans, Los Alamos

Runtime Environments

Ian Karlin, Livermore

LULESH Proxy App

Jeff Keasler, Livermore

Programming Models

Turab Lookman, Los Alamos

High Strain-Rate Applications

Enrique Martinez, Los Alamos

High Strain-Rate Applications

Jeremy Meredith, Oak Ridge

Aspen Performance Modeling

Christopher Mitchell, Los Alamos

Resource/Task Management Lead

Sue Mniszewski, Los Alamos

CoMD Proxy App

Jamal Mohd-Yusof, Los Alamos

Algorithms and Applications Co-Lead

Arun Rodrigues, Sandia

SST Performance Simulation

Barry Rountree, Livermore

GREMLIN Emulation (Power)

Martin Schulz, Livermore

Scalabale Tools Lead

Christopher Sewell, Los Alamos

CoGL Proxy App

Roger Stoller, Oak Ridge

Irradiation Applications

Jeffrey Vetter, Oak Ridge

Perf. Modeling & Simulation Lead

University Partners Collaborators from major universities

Pat Hanrahan, Stanford

Domain Specific Languages

Michael McKerns, CalTech

UQ and Runtime Systems

Houman Owhadi, CalTech

V&V and UQ Lead

Postdocs and Students Students that have contributed to the project


Ignacio Laguna, Livermore

GREMLIN Emulation (Resilience)

Frankie Li, Livermore

VPFFT Proxy App


Emmanuel Cieren, CEA

Co-Design Summer School

Zach Devito, Stanford

Terra DSL Compiler

Venmugil Elango, Ohio State

Co-Design Summer School

Riraz Haque, UCLA


Crystal Lemire, Stanford

Liszt in Terra

Robert Pavel, U. Deleware

Co-Design Summer School

Axel Rivera, U. Utah

Co-Design Summer School

Dominic Roehm, Stuttgart

Co-Design Summer School

Bertrand Rouet-Leduc, E.N.S.

Co-Design Summer School

Most of our code is released as open source // Visit the ExMatEx GitHub site