Exchange scaling of ultrafast angular momentum transfer in 4f antiferromagnets
Source abstract
Abstract
Abstract Ultrafast manipulation of magnetism bears great potential for future information technologies. While demagnetization in ferromagnets is governed by the dissipation of angular momentum1–3, materials with multiple spin sublattices, for example antiferromagnets, can allow direct angular momentum transfer between opposing spins, promising faster functionality. In lanthanides, 4fmagnetic exchange is mediated indirectly through the conduction electrons4(the Ruderman–Kittel–Kasuya–Yosida (RKKY) interaction), and the effect of such conditions on direct spin transfer processes is largely unexplored. Here, we investigate ultrafast magnetization dynamics in 4fantiferromagnets and systematically vary the 4foccupation, thereby altering the magnitude of the RKKY coupling energy. By combining time-resolved soft X-ray diffraction with ab initio calculations, we find that the rate of direct transfer between opposing moments is directly determined by this coupling. Given the high sensitivity of RKKY to the conduction electrons, our results offer a useful approach for fine tuning the speed of magnetic devices.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Magnetic properties of thin films · Advanced Condensed Matter Physics · Magnetic and transport properties of perovskites and related materials
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (41)
Show source-provided references
1. Dornes, C. et al. The ultrafast Einstein–de Haas effect. Nature 565, 209–212 (2019).10.1038/s41586-018-0822-7 ↗
2. Boeglin, C. et al. Distinguishing the ultrafast dynamics of spin and orbital moments in solids. Nature 465, 458–461 (2010).10.1038/nature09070 ↗
3. Eschenlohr, A. et al. Ultrafast spin transport as key to femtosecond demagnetization. Nat. Mater. 12, 332–336 (2013).10.1038/nmat3546 ↗
4. De Gennes, P. G. Interactions indirectes entre couches 4f dans les métaux de terres rares. J. Phys. Radium 23, 510–521 (1962).10.1051/jphysrad:01962002308-9051001 ↗
5. Jensen, J. & Mackintosh, A. R. Rare Earth Magnetism: Structures and Excitations (Clarendon Press, 1991).10.1093/oso/9780198520276.001.0001 ↗
6. Pivetta, M. et al. Measuring the intra-atomic exchange energy in rare-earth adatoms. Phys. Rev. X 10, 031054 (2020).
7. Wietstruk, M. et al. Hot-electron-driven enhancement of spin-lattice coupling in Gd and Tb 4f ferromagnets observed by femtosecond X-ray magnetic circular dichroism. Phys. Rev. Lett. 106, 127401 (2011).10.1103/PhysRevLett.106.127401 ↗
8. Rettig, L. et al. Itinerant and localized magnetization dynamics in antiferromagnetic Ho. Phys. Rev. Lett. 116, 257202 (2016).10.1103/PhysRevLett.116.257202 ↗
9. Thielemann-Kühn, N. et al. Ultrafast and energy-efficient quenching of spin order: antiferromagnetism beats ferromagnetism. Phys. Rev. Lett. 119, 197202 (2017).10.1103/PhysRevLett.119.197202 ↗
10. Windsor, Y. W. et al. Deterministic control of an antiferromagnetic spin arrangement using ultrafast optical excitation. Commun. Phys. 3, 139 (2020).10.1038/s42005-020-00407-0 ↗
11. Koopmans, B. et al. Explaining the paradoxical diversity of ultrafast laser-induced demagnetization. Nat. Mater. 9, 259–265 (2010).10.1038/nmat2593 ↗
12. Atxitia, U. & Chubykalo-Fesenko, O. Ultrafast magnetization dynamics rates within the Landau-Lifshitz-Bloch model. Phys. Rev. B 84, 144414 (2011).10.1103/PhysRevB.84.144414 ↗
13. Eriksson, O., Bergman, A., Bergqvist, L. & Hellsvik, J. Atomistic Spin Dynamics: Foundations and Applications (Oxford Univ. Press, 2017).10.1093/oso/9780198788669.001.0001 ↗
14. Holldack, K. et al. FemtoSpeX: a versatile optical pump-soft X-ray probe facility with 100 fs X-ray pulses of variable polarization. J. Synchrotron Radiat. 21, 1090–1104 (2014).10.1107/S1600577514012247 ↗
15. Roth, T. et al. Temperature dependence of laser-induced demagnetization in Ni: a key for identifying the underlying mechanism. Phys. Rev. X 2, 021006 (2012).
16. Elliott, R. J. (ed.) Magnetic Properties of Rare Earth Metals (Springer, 1972).10.1007/978-1-4757-5691-3 ↗
17. Koehler, W. C. Magnetic properties of rare‐earth metals and alloys. J. Appl. Phys. 36, 1078–1087 (1965).10.1063/1.1714108 ↗
18. De Gennes, P. G. & Saint-James, D. Helical structures of the heavy rare earth metals. Solid State Commun. 1, 62–66 (1963).10.1016/0038-1098(63)90359-4 ↗
19. de Gennes, P. G. Sur les propriétés des métaux des terres rares. C. R. Acad. Sci. 247, 1836 (1958).
20. Cywiński, Ł. & Sham, L. J. Ultrafast demagnetization in the sp–d model: a theoretical study. Phys. Rev. B 76, 45205 (2007).10.1103/PhysRevB.76.045205 ↗
21. Wang, J. et al. Femtosecond demagnetization and hot-hole relaxation in ferromagnetic Ga1–xMnxAs. Phys. Rev. B 77, 235308 (2008).10.1103/PhysRevB.77.235308 ↗
22. Frietsch, B. et al. The role of ultrafast magnon generation in the magnetization dynamics of rare-earth metals. Sci. Adv. 6, eabb1601 (2020).10.1126/sciadv.abb1601 ↗
23. Hennecke, M. et al. Angular momentum flow during ultrafast demagnetization of a ferrimagnet. Phys. Rev. Lett. 122, 157202 (2019).10.1103/PhysRevLett.122.157202 ↗
24. Bergeard, N. et al. Ultrafast angular momentum transfer in multisublattice ferrimagnets. Nat. Commun. 5, 3466 (2014).10.1038/ncomms4466 ↗
25. Mentink, J. H. et al. Ultrafast spin dynamics in multisublattice magnets. Phys. Rev. Lett. 108, 057202 (2012).10.1103/PhysRevLett.108.057202 ↗
26. Ferté, T. et al. Element-resolved ultrafast demagnetization rates in ferrimagnetic CoDy. Phys. Rev. B 96, 134303 (2017).10.1103/PhysRevB.96.134303 ↗
27. Eschenlohr, A. et al. Role of spin-lattice coupling in the ultrafast demagnetization of Gd1–xTbx alloys. Phys. Rev. B 89, 214423 (2014).10.1103/PhysRevB.89.214423 ↗
28. Ostler, T. A. et al. Ultrafast heating as a sufficient stimulus for magnetization reversal in a ferrimagnet. Nat. Commun. 3, 666 (2012).10.1038/ncomms1666 ↗
29. Ostler, T. A. et al. Crystallographically amorphous ferrimagnetic alloys: comparing a localized atomistic spin model with experiments. Phys. Rev. B 84, 24407 (2011).10.1103/PhysRevB.84.024407 ↗
30. Radu, I. et al. Transient ferromagnetic-like state mediating ultrafast reversal of antiferromagnetically coupled spins. Nature 472, 205–208 (2011).10.1038/nature09901 ↗
31. Kliemt, K. et al. Crystal growth of materials with the ThCr2Si2 structure type. Cryst. Res. Technol. 55, 1900116 (2020).10.1002/crat.201900116 ↗
32. Flechsig, U. et al. Performance measurements at the SLS SIM beamline. AIP Conf. Proc. 1234, 319–322 (2010).10.1063/1.3463200 ↗
33. Staub, U. et al. Polarization analysis in soft X-ray diffraction to study magnetic and orbital ordering. J. Synchrotron Radiat. 15, 469–476 (2008).10.1107/S0909049508019614 ↗
34. Geilhufe, M. et al. Numerical solution of the relativistic single-site scattering problem for the Coulomb and the Mathieu potential. J. Phys. Condens. Matter 27, 435202 (2015).10.1088/0953-8984/27/43/435202 ↗
35. Hoffmann, M. et al. Magnetic and electronic properties of complex oxides from first-principles. Phys. Status Solidi 257, 1900671 (2020).10.1002/pssb.201900671 ↗
36. Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).10.1103/PhysRevLett.77.3865 ↗
37. Anisimov, V. I., Zaanen, J. & Andersen, O. K. Band theory and Mott insulators: Hubbard U instead of Stoner I. Phys. Rev. B 44, 943–954 (1991).10.1103/PhysRevB.44.943 ↗
38. Liechtenstein, A. I., Katsnelson, M. I., Antropov, V. P. & Gubanov, V. A. Local spin density functional approach to the theory of exchange interactions in ferromagnetic metals and alloys. J. Magn. Magn. Mater. 67, 65–74 (1987).10.1016/0304-8853(87)90721-9 ↗
39. Wills, J. M. & Cooper, B. R. Synthesis of band and model Hamiltonian theory for hybridizing cerium systems. Phys. Rev. B 36, 3809–3823 (1987).10.1103/PhysRevB.36.3809 ↗
40. Wills, J., Eriksson, O., Alouani, M. & Price, D. in Electronic Structure and Physical Properties of Solids (ed. Dreyssé, H.) 148–167 (Springer-Verlag, 2000).
41. Wills, J. M. et al. Full-Potential Electronic Structure Method Vol. 167 (Springer-Verlag, 2010).10.1007/978-3-642-15144-6 ↗