Vampire: a software package for atomistic simulations of magnetic materials
Vampire is an open source software simulation package for atomistic simulation of magnetic materials developed at the University of York. The objective of vampire is to provide a community standard tool for atomistic simulation of magnetic materials with high performance and an easy-to-use interface.
Using a variety of common simulation methods it can calculate the equilibrium and dynamic magnetic properties of a wide variety of magnetic materials and phenomena, including ferro, ferri and antiferromagnets, core-shell nanoparticles, ultrafast spin dynamics, magnetic recording media, heat assisted magnetic recording, exchange bias, magnetic multilayer films and complete devices.
Getting vampire
Vampire is available in binary form from the offical website at vampire.york.ac.uk, or the source code is available from github. The code runs in serial and parallel on Windows, OS X and linux. The offical website now includes a comprehensive overview of the software features, as well as a manual, tutorials and example input files.
Capabilities
Vampire is designed to be highly flexible to deal with a wide variety of problems using a diverse set of simulation tools and methods. The capabilities of the code can be summarised broadly in terms of the simulation methods, standard problems, structural properties and features of the code, all of which can be combined to tackle almost any problem.
Simulation methods
- Stochastic Landau-Lifshitz-Gilbert equation (spin dynamics)
- Monte Carlo metropolis
- Constrained Monte Carlo metropolis
Standard calculations
- Ultrafast spin dynamics
- Hysteresis loops
- Curie temperature
- Temperature dependent anisotropy
- Temperature dependent energy barriers
- Field cooling
- Heat assisted and conventional magnetic recording
- Laser induced spin dynamics
Structural properties
- Bulk-like systems
- Thin films
- Nanoparticles - spheres, cubes, truncated octahedra, cylinders
- Voronoi granular structures
- Nanoparticle arrays
- Core-shell nanoparticles
- Multilayer thin films
- Interface roughness and intermixing
- Dilute magnetic systems
- Lithography defined geometries
- SC, FCC, HCP, and BCC crystal structures
- User-defined atomic structures - for example from Molecular Dynamics simulations
Magnetic properties
- Ferromagnets
- Antiferromagnets
- Ferrimagnets
- Spin glass
- Single-ion, 2-ion and cubic anisotropies
- Scalar, vector and tensor forms of exchange including the DM interaction
- User-defined Hamiltonian from ab-initio Density Functional Theory (DFT) calculations
- Demagnetisation fields (macrocell approximation)
Code features
- Modular object-oriented C++
- Simple to use textfile input
- High performance code
- Parallelisation using the MPI library
- Variety of geometric decomposition algorithms
- Usable on a laptop to a supercomputer with thousands of cores
- Output to PoVRAY for visualisation and publication quality graphics
- Output to rasmol/jmol for structural inspection
- Minimal dependence on external libraries for portability
- Freely available open source code
Using vampire
Vampire is open source software under the GPLv2 Licence and free to use for both commercial and academic research. I would ask that if you use the software please let me know as it is most helpful to know how many people/organisations are using it for their research. When citing the software please link to the vampire homepage at vampire.york.ac.uk and cite the review article of the methods implemented in vampire, Atomistic spin model simulations of magnetic nanomaterials, R F L Evans, W J Fan, P Chureemart, T A Ostler, M O A Ellis and R W Chantrell, J. Phys.: Condens. Matter 26, 103202 (2014).
