mumax is a GPU-accelerated micromagnetic simulation program developed at the 3 DyNaMat group of Prof. Van Waeyenberge at Ghent University. The code is written and maintained by Arne Vansteenkiste.
A speed-up of the order of 100x compared to CPU-based simulations can easily be reached, even with relatively inexpensive gaming GPUs. Additionally, the software is optimized for low memory use and can handle about 16 million FD cells with 2GB of GPU RAM.
Citations and licence
If you use mumax in any work or publication, we kindly ask you to cite:
"The design and verification of mumax3", AIP Advances 4, 107133 (2014)
3 is open-source software. You are free to modify and distribute the source code under the GPLv3 licence.
Web interface showing the spatial magnetization.
Landau-Lifshitz micromagnetic formalism
Arbitrary inter-region exchange like RKKY coupling
Spin-transfer torque (Zhang-Li and Slonczewski)
Uniaxial and cubic magnetocrystalline anisotropy
Thermal fluctuations (Brown)
Time- and space dependent material parameters
Arbitrary complex excitation (field, current)
Simulation window can automatically follow a moving domain wall
Edge charges can be removed to simulate an infinitely long geometry
Optional 1D, 2D or 3D periodic boundary conditions
3 includes a browser-based user interface that lets you follow a running simulation or modify it on-the-fly, be it on your local machine or remotely. simple scripting
mumax3 provides simple yet powerful input scripting. E.g., the example applies a time-dependent external field to a uniform magnet (FMR experiment).
setgridsize(128, 32, 4)
setcellsize(5e-9, 5e-9, 5e-9)
Msat = 860e3
Aex = 13e-12
m=uniform(1, 1, 0)
f := 1e9 // 1GHz
A := 0.01 // 10mT
B_ext = vector(0.1, A*sin(2*pi*f*t), 0)
Web interface can view and set parameters on-the-fly.
3 is cross-platform and runs on Linux, Windows and Mac platforms. You need an nVIDIA GPU with compute capability 2.0 or higher, as listed here.
You also need to use nVIDIA's proprietary graphics driver, which may already be installed on your system. The benchmark below may guide your GPU choice.
Mumax3 GPU perfomance for 2D simulations containing 4 million cells.