The FLEUR code[1] (also Fleur or fleur) is an open-source scientific software package for the simulation of material properties of crystalline solids, thin films, and surfaces. It implements Kohn-Sham density functional theory (DFT) in terms of the all-electron full-potential linearized augmented-plane-wave method. With this, it is a realization of one of the most precise DFT methodologies.[2] The code has the common features of a modern DFT simulation package. In the past, major applications have been in the field of magnetism, spintronics, quantum materials, e.g. in ultrathin films,[3] complex magnetism like in spin spirals or magnetic Skyrmion lattices,[4] and in spin-orbit related physics, e.g. in graphene[5] and topological insulators.[6]
Developer(s) | The FLEUR team |
---|---|
Stable release | MaX-R7.1
/ March 20, 2024 |
Repository | iffgit |
Written in | Fortran |
Operating system | Linux |
License | MIT License |
Website | www |
The physical model used in Fleur simulations is based on the (F)LAPW(+LO) method, but it is also possible to make use of an APW+lo description. The calculations employ the scalar-relativistic approximation for the kinetic energy operator.[7][8] Spin-orbit coupling can optionally be included.[9] It is possible to describe noncollinear magnetic structures periodic in the unit cell.[10] The description of spin spirals with deviating periodicity is based on the generalized Bloch theorem.[11] The code offers native support for the description of three-dimensional periodic structures, i.e., bulk crystals, as well as two-dimensional periodic structures like thin films and surfaces.[12] For the description of the exchange-correlation functional different parametrizations for the local density approximation, several generalized-gradient approximations, Hybrid functionals,[13] and partial support for the libXC library are implemented. It is also possible to make use of a DFT+U description.[14]
The Fleur code can be used to directly calculate many different material properties. Among these are:
For the calculation of optical properties Fleur can be combined with the Spex code to perform calculations employing the GW approximation to many-body perturbation theory.[18] Together with the Wannier90 library it is also possible to extract the Kohn-Sham eigenfunctions in terms of Wannier functions.[19]