FLEUR

Last updated
FLEUR
Developer(s) The FLEUR team
Stable release
MaX-R7.1 / March 20, 2024;1 day ago (2024-03-20)
Repository iffgit.fz-juelich.de/fleur/fleur
Written in Fortran
Operating system Linux
License MIT License
Website www.flapw.de

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]

Contents

Simulation model

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]

Features

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]

See also

Related Research Articles

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References

  1. ↑ Wortmann, Daniel; Michalicek, Gregor; Baadji, Nadjib; Betzinger, Markus; Bihlmayer, Gustav; Bröder, Jens; Burnus, Tobias; Enkovaara, Jussi; Freimuth, Frank; Friedrich, Christoph; Gerhorst, Christian-Roman; Granberg Cauchi, Sabastian; Grytsiuk, Uliana; Hanke, Andrea; Hanke, Jan-Philipp; Heide, Marcus; Heinze, Stefan; Hilgers, Robin; Janssen, Henning; Klüppelberg, Daniel Aaaron; Kovacik, Roman; Kurz, Philipp; Lezaic, Marjana; Madsen, Georg K. H.; Mokrousov, Yuriy; Neukirchen, Alexander; Redies, Matthias; Rost, Stefan; Schlipf, Martin; Schindlmayr, Arno; Winkelmann, Miriam; Blügel, Stefan (3 May 2023), FLEUR, Zenodo, doi:10.5281/zenodo.7576163
  2. ↑ Lejaeghere, K.; Bihlmayer, G.; Bjorkman, T.; Blaha, P.; Blugel, S.; Blum, V.; Caliste, D.; Castelli, I. E.; Clark, S. J.; Dal Corso, A.; de Gironcoli, S.; Deutsch, T.; Dewhurst, J. K.; Di Marco, I.; Draxl, C.; Dułak, M.; Eriksson, O.; Flores-Livas, J. A.; Garrity, K. F.; Genovese, L.; Giannozzi, P.; Giantomassi, M.; Goedecker, S.; Gonze, X.; Granas, O.; Gross, E. K. U.; Gulans, A.; Gygi, F.; Hamann, D. R.; Hasnip, P. J.; Holzwarth, N. A. W.; Iuşan, D.; Jochym, D. B.; Jollet, F.; Jones, D.; Kresse, G.; Koepernik, K.; Kucukbenli, E.; Kvashnin, Y. O.; Locht, I. L. M.; Lubeck, S.; Marsman, M.; Marzari, N.; Nitzsche, U.; Nordstrom, L.; Ozaki, T.; Paulatto, L.; Pickard, C. J.; Poelmans, W.; Probert, M. I. J.; Refson, K.; Richter, M.; Rignanese, G.-M.; Saha, S.; Scheffler, M.; Schlipf, M.; Schwarz, K.; Sharma, S.; Tavazza, F.; Thunstrom, P.; Tkatchenko, A.; Torrent, M.; Vanderbilt, D.; van Setten, M. J.; Van Speybroeck, V.; Wills, J. M.; Yates, J. R.; Zhang, G.-X.; Cottenier, S. (25 March 2016). "Reproducibility in density functional theory calculations of solids". Science. 351 (6280): aad3000. Bibcode:2016Sci...351.....L. doi:10.1126/science.aad3000. hdl: 1854/LU-7191263 . PMID   27013736. S2CID   206642768.
  3. ↑ Bode, M.; Heide, M.; von Bergmann, K.; Ferriani, P.; Heinze, S.; Bihlmayer, G.; Kubetzka, A.; Pietzsch, O.; Blügel, S.; Wiesendanger, R. (May 2007). "Chiral magnetic order at surfaces driven by inversion asymmetry". Nature. 447 (7141): 190–193. Bibcode:2007Natur.447..190B. doi:10.1038/nature05802. PMID   17495922. S2CID   4421433.
  4. ↑ Heinze, Stefan; von Bergmann, Kirsten; Menzel, Matthias; Brede, Jens; Kubetzka, André; Wiesendanger, Roland; Bihlmayer, Gustav; Blügel, Stefan (September 2011). "Spontaneous atomic-scale magnetic skyrmion lattice in two dimensions". Nature Physics. 7 (9): 713–718. Bibcode:2011NatPh...7..713H. doi:10.1038/nphys2045.
  5. ↑ Han, Wei; Kawakami, Roland K.; Gmitra, Martin; Fabian, Jaroslav (October 2014). "Graphene spintronics". Nature Nanotechnology. 9 (10): 794–807. arXiv: 1503.02743 . Bibcode:2014NatNa...9..794H. doi:10.1038/nnano.2014.214. PMID   25286274. S2CID   3009069.
  6. ↑ Eremeev, Sergey V.; Landolt, Gabriel; Menshchikova, Tatiana V.; Slomski, Bartosz; Koroteev, Yury M.; Aliev, Ziya S.; Babanly, Mahammad B.; Henk, Jürgen; Ernst, Arthur; Patthey, Luc; Eich, Andreas; Khajetoorians, Alexander Ako; Hagemeister, Julian; Pietzsch, Oswald; Wiebe, Jens; Wiesendanger, Roland; Echenique, Pedro M.; Tsirkin, Stepan S.; Amiraslanov, Imamaddin R.; Dil, J. Hugo; Chulkov, Evgueni V. (January 2012). "Atom-specific spin mapping and buried topological states in a homologous series of topological insulators". Nature Communications. 3 (1): 635. Bibcode:2012NatCo...3..635E. doi: 10.1038/ncomms1638 . PMID   22273673. S2CID   20501596.
  7. ↑ Koelling, D D; Harmon, B N (28 August 1977). "A technique for relativistic spin-polarised calculations". Journal of Physics C: Solid State Physics. 10 (16): 3107–3114. Bibcode:1977JPhC...10.3107K. doi:10.1088/0022-3719/10/16/019.
  8. ↑ Takeda, T. (March 1978). "The scalar relativistic approximation". Zeitschrift für Physik B. 32 (1): 43–48. Bibcode:1978ZPhyB..32...43T. doi:10.1007/BF01322185. S2CID   120097976.
  9. ↑ MacDonald, A H; Picket, W E; Koelling, D D (20 May 1980). "A linearised relativistic augmented-plane-wave method utilising approximate pure spin basis functions". Journal of Physics C: Solid State Physics. 13 (14): 2675–2683. Bibcode:1980JPhC...13.2675M. doi:10.1088/0022-3719/13/14/009.
  10. ↑ Kurz, Ph.; Förster, F.; Nordström, L.; Bihlmayer, G.; Blügel, S. (January 2004). "Ab initio treatment of noncollinear magnets with the full-potential linearized augmented plane wave method" (PDF). Physical Review B. 69 (2): 024415. Bibcode:2004PhRvB..69b4415K. doi:10.1103/PhysRevB.69.024415.
  11. ↑ Heide, M.; Bihlmayer, G.; Blügel, S. (October 2009). "Describing Dzyaloshinskii–Moriya spirals from first principles". Physica B: Condensed Matter. 404 (18): 2678–2683. Bibcode:2009PhyB..404.2678H. doi:10.1016/j.physb.2009.06.070.
  12. ↑ Krakauer, H.; Posternak, M.; Freeman, A. J. (15 February 1979). "Linearized augmented plane-wave method for the electronic band structure of thin films". Physical Review B. 19 (4): 1706–1719. Bibcode:1979PhRvB..19.1706K. doi:10.1103/PhysRevB.19.1706.
  13. ↑ Betzinger, Markus; Friedrich, Christoph; Blügel, Stefan (24 May 2010). "Hybrid functionals within the all-electron FLAPW method: Implementation and applications of PBE0". Physical Review B. 81 (19): 195117. arXiv: 1003.0524 . Bibcode:2010PhRvB..81s5117B. doi:10.1103/PhysRevB.81.195117. S2CID   119271848.
  14. ↑ Shick, A. B.; Liechtenstein, A. I.; Pickett, W. E. (15 October 1999). "Implementation of the LDA+U method using the full-potential linearized augmented plane-wave basis". Physical Review B. 60 (15): 10763–10769. arXiv: cond-mat/9903439 . Bibcode:1999PhRvB..6010763S. doi:10.1103/PhysRevB.60.10763. S2CID   119508105.
  15. ↑ Weinert, M.; Wimmer, E.; Freeman, A. J. (15 October 1982). "Total-energy all-electron density functional method for bulk solids and surfaces". Physical Review B. 26 (8): 4571–4578. Bibcode:1982PhRvB..26.4571W. doi:10.1103/PhysRevB.26.4571.
  16. ↑ Yu, Rici; Singh, D.; Krakauer, H. (15 March 1991). "All-electron and pseudopotential force calculations using the linearized-augmented-plane-wave method". Physical Review B. 43 (8): 6411–6422. Bibcode:1991PhRvB..43.6411Y. doi:10.1103/PhysRevB.43.6411. PMID   9998079.
  17. ↑ Klüppelberg, Daniel A.; Betzinger, Markus; Blügel, Stefan (5 January 2015). "Atomic force calculations within the all-electron FLAPW method: Treatment of core states and discontinuities at the muffin-tin sphere boundary". Physical Review B. 91 (3): 035105. Bibcode:2015PhRvB..91c5105K. doi:10.1103/PhysRevB.91.035105.
  18. ↑ Friedrich, Christoph; Blügel, Stefan; Schindlmayr, Arno (3 March 2010). "Efficient implementation of the G W approximation within the all-electron FLAPW method". Physical Review B. 81 (12): 125102. arXiv: 1003.0316 . Bibcode:2010PhRvB..81l5102F. doi:10.1103/PhysRevB.81.125102. S2CID   43385321.
  19. ↑ Freimuth, F.; Mokrousov, Y.; Wortmann, D.; Heinze, S.; Blügel, S. (17 July 2008). "Maximally localized Wannier functions within the FLAPW formalism". Physical Review B. 78 (3): 035120. arXiv: 0806.3213 . Bibcode:2008PhRvB..78c5120F. doi:10.1103/PhysRevB.78.035120. S2CID   53133273.
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