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The classical and quantum dynamics of molecular spins on graphene

Abstract

Controlling the dynamics of spins on surfaces is pivotal to the design of spintronic1 and quantum computing2 devices. Proposed schemes involve the interaction of spins with graphene to enable surface-state spintronics3,4 and electrical spin manipulation4,5,6,7,8,9,10,11. However, the influence of the graphene environment on the spin systems has yet to be unravelled12. Here we explore the spin–graphene interaction by studying the classical and quantum dynamics of molecular magnets13 on graphene. Whereas the static spin response remains unaltered, the quantum spin dynamics and associated selection rules are profoundly modulated. The couplings to graphene phonons, to other spins, and to Dirac fermions are quantified using a newly developed model. Coupling to Dirac electrons introduces a dominant quantum relaxation channel that, by driving the spins over Villain’s threshold, gives rise to fully coherent, resonant spin tunnelling. Our findings provide fundamental insight into the interaction between spins and graphene, establishing the basis for electrical spin manipulation in graphene nanodevices.

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Figure 1: The graphene–spin hybrids.
Figure 2: Static magnetic properties of the hybrids.
Figure 3: Classical and quantum magnetization dynamics.
Figure 4: Contributions to the zero-field spin dynamics.

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References

  1. Sanvito, S. Organic spintronics: Filtering spins with molecules. Nature Mater. 10, 484–485 (2011).

    Article  CAS  Google Scholar 

  2. DiVincenzo, D. P. Quantum computation. Science 270, 255–261 (1995).

    Article  CAS  Google Scholar 

  3. Pesin, D. & MacDonald, A. H. Spintronics and pseudospintronics in graphene and topological insulators. Nature Mater. 11, 409–416 (2012).

    Article  CAS  Google Scholar 

  4. Han, W., Kawakami, R. K., Gmitra, M. & Fabian, M. Graphene spintronics. Nature Nanotech. 9, 794–807 (2014).

    Article  CAS  Google Scholar 

  5. Garnica, M. et al. Long-range magnetic order in a purely organic 2D layer adsorbed on epitaxial graphene. Nature Phys. 9, 368–374 (2013).

    Article  CAS  Google Scholar 

  6. Nair, R. R. et al. Dual origin of defect magnetism in graphene and its reversible switching by molecular doping. Nature Commun. 4, 2010 (2013).

    Article  CAS  Google Scholar 

  7. Chen, J. J.-H., Li, L., Cullen, W. G. W., Williams, E. D. E. & Fuhrer, M. S. Tunable Kondo effect in graphene with defects. Nature Phys. 7, 535–538 (2011).

    Article  CAS  Google Scholar 

  8. Nair, R. R. et al. Spin-half paramagnetism in graphene induced by point defects. Nature Phys. 8, 199–202 (2012).

    Article  CAS  Google Scholar 

  9. Tombros, N., Jozsa, C., Popinciuc, M., Jonkman, H. T. & van Wees, B. J. Electronic spin transport and spin precession in single graphene layers at room temperature. Nature 448, 571–574 (2007).

    Article  CAS  Google Scholar 

  10. McCreary, K. M., Swartz, A. G., Han, W., Fabian, J. & Kawakami, R. J. Magnetic moment formation in graphene detected by scattering of pure spin currents. Phys. Rev. Lett. 109, 186604 (2012).

    Article  Google Scholar 

  11. Dlubak, B. et al. Highly efficient spin transport in epitaxial graphene on SiC. Nature Phys. 8, 557–561 (2012).

    Article  CAS  Google Scholar 

  12. Cervetti, C., Heintze, E. & Bogani, L. Interweaving spins with their environment: Novel inorganic nanohybrids with controllable magnetic properties. Dalton Trans. 43, 4220–4232 (2014).

    Article  CAS  Google Scholar 

  13. Gatteschi, D., Sessoli, R. & Villain, J. Molecular Nanomagnets (Oxford Univ. Press, 2006).

    Book  Google Scholar 

  14. Hueso, L. E. et al. Transformation of spin information into large electrical signals using carbon nanotubes. Nature 445, 410–413 (2007).

    Article  CAS  Google Scholar 

  15. Laird, E. A., Pei, F. & Kouwenhoven, L. P. A valley-spin qubit in a carbon nanotube. Nature Nanotech. 8, 565–568 (2013).

    Article  CAS  Google Scholar 

  16. Kuemmeth, F., Ilani, S., Ralph, D. C. & McEuen, P. L. Coupling of spin and orbital motion of electrons in carbon nanotubes. Nature 452, 448–452 (2008).

    Article  CAS  Google Scholar 

  17. Warner, M. et al. Potential for spin-based information processing in a thin-film molecular semiconductor. Nature 503, 504–508 (2013).

    Article  CAS  Google Scholar 

  18. Oberg, J. C. et al. Control of single-spin magnetic anisotropy by exchange coupling. Nature Nanotech. 9, 64–68 (2014).

    Article  CAS  Google Scholar 

  19. Mannini, M. et al. Quantum tunneling of the magnetization in a monolayer of oriented single-molecule magnets. Nature 468, 417–421 (2010).

    Article  CAS  Google Scholar 

  20. Bogani, L. et al. Single-molecule-magnets carbon-nanotube hybrids. Angew. Chem. Int. Ed. 121, 760–764 (2009).

    Article  Google Scholar 

  21. Ferrari, A. C. & Basko, D. M. Raman spectroscopy as a versatile tool for studying the properties of graphene. Nature Nanotech. 8, 235–246 (2013).

    Article  CAS  Google Scholar 

  22. Misra, S. K., Poole, C. P. & Farach, H. A. A review of spin Hamiltonian forms for various point-group site symmetries. Appl. Magn. Reson. 11, 29–46 (1996).

    Article  CAS  Google Scholar 

  23. Verniani, L. et al. Magnetic bistability of isolated giant-spin centers in a diamagnetic crystalline matrix. Chem. Eur. J. 18, 3390–3398 (2012).

    Article  Google Scholar 

  24. Repollés, A., Cornia, A. & Luis, F. Spin-lattice relaxation via quantum tunneling in diluted crystals of Fe4 single-molecule magnets. Phys. Rev. B 89, 054429 (2014).

    Article  Google Scholar 

  25. Koshino, M., Arimura, Y. & Ando, T. Magnetic field screening and mirroring in graphene. Phys. Rev. Lett. 102, 177203 (2009).

    Article  Google Scholar 

  26. Fort, A., Rettori, A., Villain, J., Gatteschi, D. & Sessoli, R. Mixed quantum-thermal relaxation in Mn12 acetate molecules. Phys. Rev. Lett. 80, 612–615 (1998).

    Article  CAS  Google Scholar 

  27. Leuenberger, M. N. & Loss, D. Spin tunneling and phonon-assisted relaxation in Mn12-acetate. Phys. Rev. B 61, 1286–1302 (2000).

    Article  CAS  Google Scholar 

  28. Trauzettel, B., Bulaev, D. V., Loss, D. & Burkard, G. Spin qubits in graphene quantum dots. Nature Phys. 3, 192–196 (2007).

    Article  CAS  Google Scholar 

  29. Lundberg, M. B., Yang, R., Renard, J. & Folk, J. A. Defect-mediated spin relaxation and dephasing in graphene. Phys. Rev. Lett. 110, 156601 (2013).

    Article  Google Scholar 

  30. Yamamoto, M. et al. Electrical control of a solid-state flying qubit. Nature Nanotech. 7, 247–251 (2012).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank J. Wrachtrup and E. Rastelli for discussions; M. Konuma, U. Stützel, J. Sesé, A. L. Barra, D. Drung, Th. Schurig and L. Sebeke for assistance with the measurements; and financial support from Italian MIUR, Spanish MINECO (MAT2012-38318-C03-01), BW-Stiftung (Kompetenznetz Funktionelle Nanostrukturen), ERC-StG-338258 ‘OptoQMol’, the Royal Society (URF fellowship and grant) and the AvH Stiftung (Sofja Kovalevskaja award).

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Contributions

C.C. performed the functionalization and most measurements. A.C. synthetized the molecules. C.C. and S.R. acquired the MALDI-TOF spectra. A.Repollés and F.L. performed the ultralow-temperature magnetic measurements. A.Rettori, M.G.P. and L.B. performed the theoretical analysis. L.B. and M.B. conceived the experiments. L.B. wrote the draft and all authors contributed to discussions and the final manuscript.

Corresponding authors

Correspondence to Christian Cervetti or Lapo Bogani.

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The authors declare no competing financial interests.

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Cervetti, C., Rettori, A., Pini, M. et al. The classical and quantum dynamics of molecular spins on graphene. Nature Mater 15, 164–168 (2016). https://doi.org/10.1038/nmat4490

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