NekCEM https://svn.mcs.anl.gov/repos/NEKCEM is a high-fidelity electromagnetic solver that has been developed at Mathematics and Computer Science Division of Argonne National Laboratory. It's an open source code, written by Misun Min, Jing Fu, Andreas Kloeckner in 1996-2011, with technical inputs from Paul Fischer  and his incompressible Navier-Stokes solver Nek5000 . The code is written in Fortran and C, using MPI for parallelism.
The code targets high performance high-order simulations on the advanced computer architectures for the applications in accelerator physics and nanoscience, predicting optimal designs of next-generation electromagnetic devices such as accelerator components for the International Linear Collider or the Large Hadron Collider, nanosensors for molecular detection, and photovoltaic solar cells with high energy-conversion efficiency.
- High-order spectral element discretizations
- Hexahedral body conforming meshes
- The 4th-order Runge-Kutta timestepping
- The high-order exponential time integration
- Light transmission calculations for nanodevices
- Wakepotential calculations for accelerator devices
- high parallel efficiency scaling over 100,000 cores
- parallel IO scaling over 65,000 cores
- Hybrid programming
- Parallel IO with pthreading
- Documentation for data file setting
- Documentation for parallel I/O
- Documentation for restart
- Documentation for how to compile/run