Electrically controlled nuclear polarization of individual atoms

Abstract

Nuclear spins serve as sensitive probes in chemistry1 and materials science2 and are promising candidates for quantum information processing3,4,5,6. NMR, the resonant control of nuclear spins, is a powerful tool for probing local magnetic environments in condensed matter systems, which range from magnetic ordering in high-temperature superconductors7,8 and spin liquids9 to quantum magnetism in nanomagnets10,11. Increasing the sensitivity of NMR to the single-atom scale is challenging as it requires a strong polarization of nuclear spins, well in excess of the low polarizations obtained at thermal equilibrium, as well as driving and detecting them individually4,5,12. Strong nuclear spin polarization, known as hyperpolarization, can be achieved through hyperfine coupling with electron spins2. The fundamental mechanism is the conservation of angular momentum: an electron spin flips and a nuclear spin flops. The nuclear hyperpolarization enables applications such as in vivo magnetic resonance imaging using nanoparticles13, and is harnessed for spin-based quantum information processing in quantum dots14 and doped silicon15,16,17. Here we polarize the nuclear spins of individual copper atoms on a surface using a spin-polarized current in a scanning tunnelling microscope. By employing the electron–nuclear flip-flop hyperfine interaction, the spin angular momentum is transferred from tunnelling electrons to the nucleus of individual Cu atoms. The direction and magnitude of the nuclear polarization is controlled by the direction and amplitude of the current. The nuclear polarization permits the detection of the NMR of individual Cu atoms, which is used to sense the local magnetic environment of the Cu electron spin.

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Fig. 1: Electrical polarization of the nuclear spin of a Cu atom on MgO.
Fig. 2: Electronic and hyperfine structures of a single Cu atom on MgO.
Fig. 3: Spin-transfer torque of the Cu nuclear spin.
Fig. 4: NMR-type transitions of single Cu atoms.

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding authors upon reasonable request.

References

  1. 1.

    Staudacher, T. et al. Nuclear magnetic resonance spectroscopy on a (5-nanometer)3 sample volume. Science 339, 561–563 (2013).

    CAS  Article  Google Scholar 

  2. 2.

    Slichter, C. P. Principles of Magnetic Resonance (Springer, Heidelberg, 1996).

  3. 3.

    Morley, G. W. et al. Quantum control of hybrid nuclear–electronic qubits. Nat. Mater. 12, 103–107 (2013).

    CAS  Article  Google Scholar 

  4. 4.

    Thiele, S. et al. Electrically driven nuclear spin resonance in single-molecule magnets. Science 344, 1135–1138 (2014).

    CAS  Article  Google Scholar 

  5. 5.

    Pla, J. J. et al. High-fidelity readout and control of a nuclear spin qubit in silicon. Nature 496, 334–338 (2013).

    CAS  Article  Google Scholar 

  6. 6.

    Sigillito, A. J. et al. All-electric control of donor nuclear spin qubits in silicon. Nat. Nanotech. 12, 958–962 (2017).

    CAS  Article  Google Scholar 

  7. 7.

    Alloul, H., Ohno, T. & Mendels, P. 89Y NMR evidence for a Fermi-liquid behavior in YBa2Cu3O6+x. Phys. Rev. Lett. 63, 1700–1703 (1989).

    CAS  Article  Google Scholar 

  8. 8.

    Wu, T. et al. Magnetic-field-induced charge-stripe order in the high-temperature superconductor YBa2Cu3Oy. Nature 477, 191–194 (2011).

    CAS  Article  Google Scholar 

  9. 9.

    Mendels, P. et al. Ga NMR study of the local susceptibility in kagomé-based SrCr8Ga4O19: pseudogap and paramagnetic defects. Phys. Rev. Lett. 85, 3496–3499 (2000).

    CAS  Article  Google Scholar 

  10. 10.

    Borsa, F., Lascialfari, A. & Furukawa, Y. Novel NMR and EPR Techniques (eds Dolinšek, J., Vilfan, M. & Žumer, S.) 297–349 (Springer, Heidelberg, 2006).

  11. 11.

    Micotti, E. et al. Local spin moment distribution in antiferromagnetic molecular rings probed by NMR. Phys. Rev. Lett. 97, 267204 (2006).

    CAS  Article  Google Scholar 

  12. 12.

    Dutt, M. V. G. et al. Quantum register based on individual electronic and nuclear spin qubits in diamond. Science 316, 1312–1316 (2007).

    Article  Google Scholar 

  13. 13.

    Cassidy, M. C. et al. In vivo magnetic resonance imaging of hyperpolarized silicon particles. Nat. Nanotech. 8, 363–368 (2013).

    CAS  Article  Google Scholar 

  14. 14.

    Urbaszek, B. et al. Nuclear spin physics in quantum dots: an optical investigation. Rev. Mod. Phys. 85, 79–133 (2013).

    CAS  Article  Google Scholar 

  15. 15.

    McCamey, D. R., van Tol, J., Morley, G. W. & Boehme, C. Fast nuclear spin hyperpolarization of phosphorus in silicon. Phys. Rev. Lett. 102, 027601 (2009).

    CAS  Article  Google Scholar 

  16. 16.

    Simmons, S. et al. Entanglement in a solid-state spin ensemble. Nature 470, 69–72 (2011).

    CAS  Article  Google Scholar 

  17. 17.

    Morley, G. W. et al. The initialization and manipulation of quantum information stored in silicon by bismuth dopants. Nat. Mater. 9, 725–729 (2010).

    CAS  Article  Google Scholar 

  18. 18.

    Smet, J. H. et al. Gate-voltage control of spin interactions between electrons and nuclei in a semiconductor. Nature 415, 281–286 (2002).

    CAS  Article  Google Scholar 

  19. 19.

    Lo, C. C. et al. All-electrical nuclear spin polarization of donors in silicon. Phys. Rev. Lett. 110, 057601 (2013).

    CAS  Article  Google Scholar 

  20. 20.

    Trowbridge, C. J. et al. Dynamic nuclear polarization from current-induced electron spin polarization. Phys. Rev. B 90, 085122 (2014).

    Article  Google Scholar 

  21. 21.

    Paul, W. et al. Control of the millisecond spin lifetime of an electrically probed atom. Nat. Phys. 13, 403–407 (2017).

    CAS  Article  Google Scholar 

  22. 22.

    Ting, Y. & Lew, H. Hyperfine structure of Cu63 and Cu65. Phys. Rev. 105, 581–588 (1957).

    CAS  Article  Google Scholar 

  23. 23.

    Heinrich, A. J., Gupta, J. A., Lutz, C. P. & Eigler, D. M. Single-atom spin-flip spectroscopy. Science 306, 466–469 (2004).

    CAS  Article  Google Scholar 

  24. 24.

    Baumann, S. et al. Electron paramagnetic resonance of individual atoms on a surface. Science 350, 417–420 (2015).

    CAS  Article  Google Scholar 

  25. 25.

    Yang, K. et al. Engineering the eigenstates of coupled spin-1/2 atoms on a surface. Phys. Rev. Lett. 119, 227206 (2017).

    Article  Google Scholar 

  26. 26.

    Willke, P. et al. Hyperfine interaction of individual atoms on a surface. Science 362, 336–339 (2018).

    CAS  Article  Google Scholar 

  27. 27.

    Otte, A. F. et al. The role of magnetic anisotropy in the Kondo effect. Nat. Phys. 4, 847–850 (2008).

    CAS  Article  Google Scholar 

  28. 28.

    McGarvey, B. R. The isotropic hyperfine interaction. J. Phys. Chem. 71, 51–66 (1967).

    CAS  Article  Google Scholar 

  29. 29.

    Loth, S. et al. Controlling the state of quantum spins with electric currents. Nat. Phys. 6, 340–344 (2010).

    CAS  Article  Google Scholar 

  30. 30.

    Reimer, J. A. Nuclear hyperpolarization in solids and the prospects for nuclear spintronics. Solid. State Nucl. Magn. Reson. 37, 3–12 (2010).

    CAS  Article  Google Scholar 

  31. 31.

    Wolfowicz, G. et al. Atomic clock transitions in silicon-based spin qubits. Nat. Nanotech. 8, 561–564 (2013).

    CAS  Article  Google Scholar 

  32. 32.

    Shiddiq, M. et al. Enhancing coherence in molecular spin qubits via atomic clock transitions. Nature 531, 348–351 (2016).

    CAS  Article  Google Scholar 

  33. 33.

    Heinrich, B. W., Braun, L., Pascual, J. I. & Franke, K. J. Protection of excited spin states by a superconducting energy gap. Nat. Phys. 9, 765–768 (2013).

    CAS  Article  Google Scholar 

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Acknowledgements

We thank B. Melior for expert technical assistance. We acknowledge financial support from the Office of Naval Research. P.W., Y.B. and A.J.H. acknowledge support from Institute for Basic Science under IBS-R027-D1. P.W. acknowledges support from the Alexander von Humboldt Foundation. A.F. acknowledges CONICET (PIP11220150100327 and PUE-22920170100089CO). J.L.L. thanks the ETH Fellowship program for financial support. J.F.-R. thanks FCT, under the project PTDC/FIS-NAN/4662/2014.

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K.Y. and C.P.L. designed the experiment. K.Y., P.W. and Y.B. carried out the STM measurements. K.Y. and C.P.L. performed the analysis and developed the rate equation model. A.F., J.L.L. and J.F.-R. performed the DFT calculations. All the authors discussed the results and edited the manuscript.

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Correspondence to Andreas J. Heinrich or Christopher P. Lutz.

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Yang, K., Willke, P., Bae, Y. et al. Electrically controlled nuclear polarization of individual atoms. Nature Nanotech 13, 1120–1125 (2018). https://doi.org/10.1038/s41565-018-0296-7

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