SFB 668: Magnetism from the Single Atom to the Nanostructure
Chemistry
Final Report Abstract
In the framework of our Collaborative Research Center 668 „Magnetism from Single Atoms to Nanostructures“ we concentrated on fundamental studies of the static spin structure as well as the dynamic magnetic behavior of atoms, molecules, clusters, nanoparticles, nanowires, and lateral nanostructures in contact with surfaces. Though the focus of our research was on fundamental aspects of magnetism down to the atomic scale, the results will be of considerable importance with respect to future applications, for instance, for magnetic sensors, magnetic storage systems and logic elements. In order to be able to reveal magnetic properties down to the atomic scale we developed several new experimental methods, such as single-atom magnetometry for measuring the magnetization of individual atoms and molecules on surfaces, or magnetic exchange force microscopy for imaging atomic-scale spin structures on surfaces of electrically insulating materials. Furthermore, we developed several experimental methods for the investigation of the dynamic behaviour of individual magnetic atoms and nanostructures, for instance, time-resolved spin-polarized scanning tunneling microscopy, time-resolved scanning electron microscopy with polarization analysis, or time-resolved X-ray microscopy techniques. In parallel to the development of new experimental methods for the investigation of magnetism on the atomic- and nano-scale, we pushed forward the theoretical tools for treating atomic-scale magnetic systems interacting with surfaces. For more complex magnetic systems we applied appropriate simulation tools for describing their behavior on the relevant length and time scales. Based on the world-wide leading position of our Collaborative Research Center with respect to investigations of atomic and nano-scale magnetic systems we could make several fundamental discoveries, such as chiral spin spirals, magnetic skyrmion lattices and individual nano-scale magnetic skyrmions in ultrathin magnetic films stabilized by interfacial Dzyaloshinskii-Moriya (DM) interactions. Thereby, we have established the novel field of skyrmion-based spintronics which aims at the use of individual skyrmions for magnetic storage and logic applications. Furthermore, by making use of the novel technique of single-atom magnetometry, we could quanti- tatively determine magnetic moments and magnetic anisotropies of single atoms on surfaces, as well as the distance- and direction-dependence of the indirect magnetic exchange and Dzyaloshinskii-Moriya (DM) interactions down to the atomic scale. Based on this knowledge, we could design and ultimately experimentally realize tailored nanomagnets as well as all-spin atomic-scale logic devices, built up atom-by-atom, thereby demonstrating the ultimate limits of miniaturization of magnetic devices. Simultaneously, we could observe the dynamics of atomic- scale magnetic systems on their intrinsic time scales. Another highlight of our research in the framework of this Collaborative Research Center was the first atomic-scale observation of the spin structure of individual molecular orbitals and the dependence on the molecule-surface interaction. Finally, we achieved the first real-space imaging of the atomic-scale spin structure of surfaces of insulators based on the novel method of magnetic exchange force microscopy. In conclusion, our Collaborative Research Center has contributed significantly to the internationally lively field of nanomagnetism and spintronics and has even initiated new research directions.
Publications
- Atomic spin structure of antiferromagnetic domain walls. Nature Materials 5, 477 (2006)
M. Bode, E. Y. Vedmedenko, K. von Bergmann, A. Kubetzka, P. Ferriani, S. Heinze, and R. Wiesendanger
(See online at https://doi.org/10.1038/nmat1646) - Chiral magnetic order at surfaces driven by inversion asymmetry. Nature 447, 190 (2007)
M. Bode, M. Heide, K. von Bergmann, P. Ferriani, S. Heinze, G. Bihlmayer, A. Kubetzka, O. Pietzsch, S. Blügel, and R. Wiesendanger
(See online at https://doi.org/10.1038/nature05802) - Current-induced magnetization switching with a spin-polarized scanning tunneling microscope. Science 317, 1537 (2007)
S. Krause, L. Berbil-Bautista, G. Herzog, M. Bode, and R. Wiesendanger
(See online at https://doi.org/10.1126/science.1145336) - Magnetic exchange force microscopy with atomic resolution. Nature 446, 522 (2007)
U. Kaiser, A. Schwarz, and R. Wiesendanger
(See online at https://doi.org/10.1038/nature05617) - Atomically resolved mechanical response of individual metallofullerene molecules confined inside carbon nanotubes. Nature Nanotechnology 3, 337 (2008)
M. Ashino, D. Obergfell, M. Haluska, S. Yang, A. N. Khlobystov, S. Roth, and R. Wiesendanger
(See online at https://doi.org/10.1038/nnano.2008.126) - Half-metallic ferromagnets: From band structure to many-body effects. Rev. Mod. Phys. 80, 315 (2008)
M. I. Katsnelson, V. Yu. Irkhin, L. Chioncel, A. I. Lichtenstein, and R. A. de Groo
(See online at https://doi.org/10.1103/RevModPhys.80.315) - Nanomechanical detection of itinerant electron spin flip. Nature Nanotechnology 3, 720 (2008)
G. Zolfagharkhani, A. Gaidarzhy, P. Degiovanni, S. Kettemann, P. Fulde, and P. Mohanty
(See online at https://doi.org/10.1038/nnano.2008.311) - Revealing magnetic interactions from single-atom magnetization curves. Science 320, 82 (2008)
F. Meier, L. Zhou, J. Wiebe, and R. Wiesendanger
(See online at https://doi.org/10.1126/science.1154415) - Single-shot terahertz-field-driven X-ray streak camera. Nature Photonics 3, 523 (2009)
U. Frühling, M. Wieland, M. Gensch, T. Gebert, B. Schütte, M. Krikunova, R. Kalms, F. Budzyn, O. Grimm, J. Rossbach, E. Plönjes, and M. Drescher
(See online at https://doi.org/10.1038/nphoton.2009.160) - Spin mapping at the nanoscale and atomic scale. Rev. Mod. Phys. 81, 1495 (2009)
R. Wiesendanger
(See online at https://doi.org/10.1103/RevModPhys.81.1495) - Detecting excitation and magnetization of individual dopants in a semiconductor. Nature 467, 1084 (2010)
A.A. Khajetoorians, B. Chilian, J. Wiebe, S. Schuwalow, F. Lechermann, and R. Wiesendanger
(See online at https://doi.org/10.1038/nature09519) - Imaging and manipulating the spin direction of individual atoms. Nature Nanotechnology 5, 350 (2010)
D. Serrate, P. Ferriani, Y. Yoshida, S.-W. Hla, M. Menzel, K. von Bergmann, S. Heinze, A. Kubetzka, and R. Wiesendanger
(See online at https://doi.org/10.1038/nnano.2010.64) - Strength and directionality of surface Ruderman-Kittel-Kasuya-Yosida interaction mapped on the atomic scale. Nature Physics 6, 187 (2010)
L. Zhou, J. Wiebe, S. Lounis, E. Vedmedenko, F. Meier, S. Blügel, P. H. Dederichs, and R. Wiesendanger
(See online at https://doi.org/10.1038/nphys1514) - Continuous-time Monte Carlo methods for quantum impurity models. Rev. Mod. Phys. 83, 349 (2011)
E. Gull, A. J. Millis, A. I. Lichtenstein, A. N. Rubtsov, M. Troyer, and P. Werner
(See online at https://doi.org/10.1103/RevModPhys.83.349) - Realizing all-spin-based logic operations atom by atom. Science 332, 1062 (2011)
A.A. Khajetoorians, J. Wiebe, B. Chilian, and R. Wiesendanger
(See online at https://doi.org/10.1126/science.1201725) - Spontaneous atomic-scale magnetic skyrmion lattice in two dimensions. Nature Physics 7, 713 (2011)
S. Heinze, K. von Bergmann, M. Menzel, J. Brede, A. Kubetzka, R. Wiesendanger, G. Bihlmayer, and S. Blügel
(See online at https://doi.org/10.1038/nphys2045) - Tunable negligible-loss energy transfer between dipolar-coupled magnetic disks by stimulated vortex gyration. Scientific Reports 1, 59 (2011)
H. Jung, K.-S. Lee, D.-E. Jeong, Y.-S. Choi, Y.-S. Yu, D.-S. Han, A. Vogel, L. Bocklage, G. Meier, M.-Y. Im, P. Fischer, and S.-K. Kim
(See online at https://doi.org/10.1038/srep00059) - Atom-by-atom engineering and magnetometry of tailored nanomagnets. Nature Physics 8, 497 (2012)
A. A. Khajetoorians, J. Wiebe, B. Chilian, S. Lounis, S. Blügel, and R. Wiesendanger
(See online at https://doi.org/10.1038/nphys2299) - Real-space observation of spin-split molecular orbitals of adsorbed singlemolecule magnets. Nature Communications 3, 953 (2012)
J. Schwöbel, Y. Fu, J. Brede, A. Dilullo, G. Hoffmann, S. Klyatskaya, M. Ruben, and R. Wiesendanger
(See online at https://doi.org/10.1038/ncomms1953) - Ultrafast optical demagnetization manipulates nanoscale spin structure in domain walls. Nature Communications 3, 1100 (2012)
B. Pfau, S. Schaffert, L. Müller, C. Gutt, A. Al-Shemmary, F. Büttner, R. Delaunay, S. Düsterer, S. Flewett, R. Frömter, J. Geilhufe, E. Guehrs, C.M. Günther, R. Hawaldar, M. Hille, N. Jaouen, A. Kobs, K. Li, J. Mohanty, H. Redlin, W.F. Schlotter, D. Stickler, R. Treusch, B. Vodungbo, M. Kläui, H.P. Oepen, J. Lüning, G. Grübel, and S. Eisebitt
(See online at https://doi.org/10.1038/ncomms2108) - Current-driven spin dynamics of artificially constructed quantum magnets. Science 339, 6115 (2013)
A. A. Khajetoorians, B. Baxevanis, C. Hübner, T. Schlenk, S. Krause, T. O. Wehling, S. Lounis, A. Lichtenstein, D. Pfannkuche, J. Wiebe, and R. Wiesendanger
(See online at https://doi.org/10.1126/science.1228519) - Time-resolved imaging of nonlinear magnetic domain-wall dynamics in ferromagnetic nanowires. Scientific Reports 3, 1737 (2013)
F.-U. Stein, L. Bocklage, M. Weigand, and G. Meier
(See online at https://doi.org/10.1038/srep01737) - Wave modes of collective vortex gyration in dipolar-coupled-dot-array magnonic crystals. Scientific Reports 3, 2262 (2013)
D.-S. Han, A. Vogel, H. Jung, K.-S. Lee, M. Weigand, H. Stoll, G. Schütz, P. Fischer, G. Meier and S.-K. Kim
(See online at https://doi.org/10.1038/srep02262) - Writing and deleting single magnetic skyrmions. Science 341, 636 (2013)
N. Romming, C. Hanneken, M. Menzel, J. E. Bickel, B. Wolter, K. von Bergmann, A. Kubetzka, and R. Wiesendanger
(See online at https://doi.org/10.1126/science.1240573) - Long-range magnetic coupling between nanoscale organic-metal hybrids mediated by a nanoskyrmion lattice. Nature Nanotechnology 9, 1018 (2014)
J. Brede, N. Atodiresei, V. Caciuc, M. Bazarnik, A. Al-Zubi, S. Blügel, and R. Wiesendanger
(See online at https://doi.org/10.1038/nnano.2014.235) - Spin-resolved imaging and spectroscopy of individual molecules with sub-molecular spatial resolution. MRS Bulletin 39, 608 (2014)
J. Brede and R. Wiesendanger
(See online at https://doi.org/10.1557/mrs.2014.127) - Stochastic formation of magnetic vortex structures in asymmetric disks triggered by chaotic dynamics. Nature Communications 5, 5620 (2014)
M.-Y. Im, K.-S. Lee, A. Vogel, J.-I. Hong, G. Meier, and P. Fischer
(See online at https://doi.org/10.1038/ncomms6620) - Electrical detection of magnetic skyrmions by tunnelling non-collinear magnetoresistance. Nature Nanotechnology 10, 1039 (2015)
C. Hanneken, F. Otte, A. Kubetzka, B. Dupé, N. Romming, K. von Bergmann, R. Wiesendanger, and S. Heinze
(See online at https://doi.org/10.1038/nnano.2015.218) - Imaging spin dynamics on the nanoscale using X-Ray microscopy. Front. Phys. 3, 26 (2015)
H. Stoll, M. Noske, M. Weigand, K. Richter, B. Krüger, R. M. Reeve, M. Hänze, C.F. Adolff, F.-U. Stein, G. Meier, M. Kläui and G. Schütz
(See online at https://doi.org/10.3389/fphy.2015.00026) - Magnetic interactions in strongly correlated systems: Spin and orbital contributions. Annals of Physics 360, 61 (2015)
A. Secchia, A.I. Lichtenstein, and M.I. Katsnelson
(See online at https://doi.org/10.1016/j.aop.2015.05.002) - Stability of single skyrmionic bits. Nature Communications 6, 8455 (2015)
J. Hagemeister, N. Romming, K. von Bergmann, E.Y. Vedmedenko, and R. Wiesendanger
(See online at https://doi.org/10.1038/ncomms9455) - Tuning emergent magnetism in a Hund's impurity. Nature Nanotechnology 10, 958 (2015)
A. A. Khajetoorians, M. Valentyuk, M. Steinbrecher, T. Schlenk, A. Shick, J. Kolorenc, A. I. Lichtenstein, T. O. Wehling, R. Wiesendanger and J. Wiebe
(See online at https://doi.org/10.1038/nnano.2015.193) - Absence of a spin-signature from a single Ho adatom as probed by spin-sensitive tunneling. Nature Communications 7, 10454 (2016)
M. Steinbrecher, A. Sonntag, M. dos Santos Dias, M. Bouhassoune, S. Lounis, J. Wiebe, R. Wiesendanger, and A. A. Khajetoorians
(See online at https://doi.org/10.1038/ncomms10454) - Collective modes in threedimensional magnonic vortex crystals. Scientific Reports 6, 22402 (2016)
M. Hänze, C. F. Adolff, B. Schulte, J. Möller, M. Weigand, and G. Meier
(See online at https://doi.org/10.1038/srep22402) - Direct observation of isolated Damon-Eshbach and backward volume spin-wave packets in ferromagnetic microstripes. Scientific Reports 6, 22117 (2016)
P. Wessels, A. Vogel, J.-N. Tödt, M. Wieland G. Meier, and M. Drescher
(See online at https://doi.org/10.1038/srep22117) - Nanoscale magnetic skyrmions in metallic films and multilayers: a new twist for spintronics. Nature Reviews Materials 1, 16044 (2016)
R. Wiesendanger
(See online at https://doi.org/10.1038/natrevmats.2016.44) - Tailoring the chiral magnetic interaction between two individual atoms. Nature Communications 7, 10620 (2016)
A. A. Khajetoorians, M. Steinbrecher, M. Ternes, M. Bouhassoune, M. dos Santos Dias, S. Lounis, J. Wiebe, and R. Wiesendanger
(See online at https://doi.org/10.1038/ncomms10620) - A gateway towards non-collinear spin processing using three-atom magnets with strong substrate coupling. Nature Communications 8, 642 (2017)
J. Hermenau, J. Ibañez-Azpiroz, Chr. Hübner, A. Sonntag, B. Baxevanis, K. T. Ton, M. Steinbrecher, A. A. Khajetoorians, M. dos Santos Dias, S. Blügel, R. Wiesendanger, S. Lounis, and J. Wiebe
(See online at https://doi.org/10.1038/s41467-017-00506-7) - Electric-field-driven switching of individual magnetic Skyrmions. Nature Nanotechnology 12, 123 (2017)
P.-J. Hsu, A. Kubetzka, A. Finco, N. Romming, K. von Bergmann, and R. Wiesendanger
(See online at https://doi.org/10.1038/nnano.2016.234) - Towards colloidal spintronics through Rashba spin-orbit interaction in lead sulphide nanosheets. Nature Communications 8, 15721 (2017)
M. M. R. Moayed, T. Bielewicz, M. S. Zöllner, C. Herrmann, and C. Klinke
(See online at https://doi.org/10.1038/ncomms15721)
