Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Spin excitations in a single La2CuO4 layer

Nature Materials volume 11, pages 850–854 (2012)Cite this article

Subjects

Abstract

Cuprates and other high-temperature superconductors consist of two-dimensional layers that are crucial to their properties. The dynamics of the quantum spins in these layers lie at the heart of the mystery of the cuprates1,2,3,4,5,6,7. In bulk cuprates such as La2CuO4, the presence of a weak coupling between the two-dimensional layers stabilizes a three-dimensional magnetic order up to high temperatures. In a truly two-dimensional system however, thermal spin fluctuations melt long-range order at any finite temperature8. Here, we measure the spin response of isolated layers of La2CuO4 that are only one-unit-cell-thick. We show that coherent magnetic excitations, magnons, known from the bulk order, persist even in a single layer of La2CuO4, with no evidence for more complex correlations such as resonating valence bond correlations9,10,11. These magnons are, therefore, well described by spin-wave theory (SWT). On the other hand, we also observe a high-energy magnetic continuum in the isotropic magnetic response that is not well described by two-magnon SWT, or indeed any existing theories.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: The scattering geometry, a schematic of the samples and a typical RIXS spectrum.
Figure 2: Magnetic dispersions of isolated and coupled La2CuO4 layers.
Figure 3: Magnon peak showing anisotropic high-energy magnetic scattering.
Figure 4: Scaling of the magnetic excitations.

Similar content being viewed by others

References

  1. Hayden, S. M., Mook, H. A., Dai, P., Perring, T. G. & Dogan, F. The structure of the high-energy spin excitations in a high-transition-temperature superconductor. Nature 429, 531–534 (2004).

    Article  CAS  Google Scholar 

  2. Vignolle, B. et al. Two energy scales in the spin excitations of the high-temperature superconductor La2−xSrxCuO4 . Nature Phys. 3, 163–167 (2007).

    Article  CAS  Google Scholar 

  3. Li, Y. et al. Hidden magnetic excitation in the pseudogap phase of a high- Tc superconductor. Nature 468, 283–285 (2010).

    Article  CAS  Google Scholar 

  4. Le Tacon, M. et al. Intense paramagnon excitations in a large family of high-temperature superconductors. Nature Phys. 7, 725–730 (2011).

    Article  CAS  Google Scholar 

  5. Coldea, R. et al. Spin waves and electronic interactions in La2CuO4 . Phys. Rev. Lett. 86, 5377–5380 (2001).

    Article  CAS  Google Scholar 

  6. Headings, N. S., Hayden, S. M., Coldea, R. & Perring, T. G. Anomalous high-energy spin excitations in the high- T c superconductor-parent antiferromagnet La2CuO4 . Phys. Rev. Lett. 105, 247001 (2010).

    Article  CAS  Google Scholar 

  7. Braicovich, L. et al. Magnetic excitations and phase separation in the underdoped La2−xSrxCuO4 superconductor measured by resonant inelastic X-ray scattering. Phys. Rev. Lett. 104, 077002 (2010).

    Article  CAS  Google Scholar 

  8. Mermin, N. D. & Wagner, H. Absence of ferromagnetism or antiferromagnetism in one- or two-dimensional isotropic Heisenberg models. Phys. Rev. Lett. 17, 1133–1136 (1966).

    Article  CAS  Google Scholar 

  9. Christensen, N. B. et al. Quantum dynamics and entanglement of spins on a square lattice. Proc. Natl Acad. Sci. USA 104, 15264–15269 (2007).

    Article  CAS  Google Scholar 

  10. Anderson, P. W. The resonating valence bond state in La2CuO4 and superconductivity. Science 235, 1196–1198 (1987).

    Article  CAS  Google Scholar 

  11. Hsu, T. C. Spin waves in the flux-phase description of the S = 1/2 Heisenberg antiferromagnet. Phys. Rev. B 41, 11379–11387 (1990).

    Article  CAS  Google Scholar 

  12. Manousakis, E. The spin-1/2 heisenberg antiferromagnet on a square lattice and its application to the cuprous oxides. Rev. Mod. Phys. 63, 1–62 (1991).

    Article  CAS  Google Scholar 

  13. Keimer, B. et al. Magnetic excitations in pure, lightly doped, and weakly metallic La2CuO4 . Phys. Rev. B 46, 14034–14053 (1992).

    Article  CAS  Google Scholar 

  14. Chakravarty, S., Halperin, B. & Nelson, D. Two-dimensional quantum Heisenberg antiferromagnet at low temperatures. Phys. Rev. B 39, 2344–2371 (1989).

    Article  CAS  Google Scholar 

  15. Sandvik, A. & Singh, R. High-energy magnon dispersion and multimagnon continuum in the two-dimensional Heisenberg antiferromagnet. Phys. Rev. Lett. 86, 528–531 (2001).

    Article  CAS  Google Scholar 

  16. Ho, C-M., Muthukumar, V., Ogata, M. & Anderson, P. Nature of spin excitations in two-dimensional Mott insulators: Undoped cuprates and other materials. Phys. Rev. Lett. 86, 1626–1629 (2001).

    Article  CAS  Google Scholar 

  17. Suter, A. et al. Two-dimensional magnetic and superconducting phases in metal–insulator La2−xSrxCuO4 superlattices measured by muon-spin rotation. Phys. Rev. Lett. 106, 237003 (2011).

    Article  CAS  Google Scholar 

  18. Schlappa, J. et al. Collective magnetic excitations in the spin ladder Sr14Cu24O41 measured using high-resolution resonant inelastic X-ray scattering. Phys. Rev. Lett. 103, 047401 (2009).

    Article  CAS  Google Scholar 

  19. Guarise, M. et al. Measurement of magnetic excitations in the two-dimensional antiferromagnetic Sr2CuO2Cl2 insulator using resonant X-ray scattering: Evidence for extended interactions. Phys. Rev. Lett. 105, 157006 (2010).

    Article  CAS  Google Scholar 

  20. Ament, L. J. P., van Veenendaal, M., Devereaux, T. P., Hill, J. P. & van den Brink, J. Resonant inelastic X-ray scattering studies of elementary excitations. Rev. Mod. Phys. 83, 705–767 (2011).

    Article  CAS  Google Scholar 

  21. Schlappa, J. et al. Spin-orbital separation in the quasi-one-dimensional Mott insulator Sr2CuO3 . Nature 485, 82–85 (2012).

    Article  CAS  Google Scholar 

  22. Dalla Piazza, B. et al. Unified one-band Hubbard model for magnetic and electronic spectra of the parent compounds of cuprate superconductors. Phys. Rev. B 85, 100508 (2012).

    Article  Google Scholar 

  23. Rønnow, H. et al. Spin dynamics of the 2D spin 1/2 quantum antiferromagnet copper deuteroformate tetradeuterate (CFTD). Phys. Rev. Lett. 87, 037202 (2001).

    Article  Google Scholar 

  24. Singh, R. R. P. & Gelfand, M. P. Spin-wave excitation spectra and spectral weights in square lattice antiferromagnets. Phys. Rev. B 52, R15695–R15698 (1995).

    Article  Google Scholar 

  25. Ament, L. J. P. & van den Brink, J. Strong three-magnon scattering in cuprates by resonant X-rays, Preprint at http://arxiv.org/abs/1002.3773 (2010).

  26. Igarashi, J-i. & Nagao, T. Magnetic excitations in l-edge resonant inelastic X-ray scattering from cuprate compounds. Phys. Rev. B 85, 064421 (2012).

    Article  Google Scholar 

  27. Ament, L., Ghiringhelli, G., Sala, M., Braicovich, L. & van den Brink, J. Theoretical demonstration of how the dispersion of magnetic excitations in cuprate compounds can be determined using resonant inelastic X-ray scattering. Phys. Rev. Lett. 103, 117003 (2009).

    Article  Google Scholar 

  28. Haverkort, M. W. Theory of resonant inelastic X-ray scattering by collective magnetic excitations. Phys. Rev. Lett. 105, 167404 (2010).

    Article  CAS  Google Scholar 

  29. Huberman, T. et al. Two-magnon excitations observed by neutron scattering in the two-dimensional spin-5/2 Heisenberg antiferromagnet Rb2MnF4 . Phys. Rev. B 72, 014413 (2005).

    Article  Google Scholar 

  30. Gozar, A. et al. High-temperature interface superconductivity between metallic and insulating copper oxides. Nature 455, 782–785 (2008).

    Article  CAS  Google Scholar 

  31. Logvenov, G., Gozar, A. & Božović, I. High-temperature superconductivity in a single copper–oxygen plane. Science 326, 699–702 (2009).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank R. Konik, M. Haverkort, A. Boothroyd and G. Luke for fruitful discussions, X. Liu for assistance with the sample characterization and S. Hayden and R. Coldea for sharing their data in ref. 6. The experiment was performed at the ADRESS beamline of the Swiss Light Source using the SAXES instrument jointly built by the Paul Scherrer Institut, Switzerland and the Politecnico di Milano, Italy. We acknowledge V. Strocov for support at the ADRESS beamline and A. Suter and T. Prokscha for their assistance with the muon spin rotation measurements. Work at Brookhaven National Laboratory was supported by the Office of Basic Energy Sciences, Division of Materials Science and Engineering, US Department of Energy under Award No. DEAC02-98CH10886. M.P.M.D. and J.P.H. are supported by the Center for Emergent Superconductivity, an Energy Frontier Research Center funded by the US DOE, Office of Basic Energy Sciences. C.M., K.J.Z and T.S. acknowledge support from the Swiss National Science Foundation and its NCCR MaNEP.

Author information

Author notes

  1. K. J. Zhou and J. Pereiro is a Present addresses: Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK (K.J.Z.); Department of Physics, University of California, San Diego, La Jolla, California 92093, USA (J.P.)

Authors and Affiliations

  1. Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, New York 11973, USA

    M. P. M. Dean, J. Pereiro, I. Božović & J. P. Hill

  2. London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, London WC1E 6BT, UK

    R. S. Springell

  3. Royal Commission for the Exhibition of 1851 Research Fellow, Interface Analysis Centre, University of Bristol, Bristol BS2 8BS, UK

    R. S. Springell

  4. Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland

    C. Monney, K. J. Zhou & T. Schmitt

  5. Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Switzerland

    B. Dalla Piazza & H. M. Rønnow

  6. Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland

    E. Morenzoni

  7. Institute for Theoretical Solid State Physics, IFW Dresden, D01171 Dresden, Germany

    J. van den Brink

Authors
  1. M. P. M. Dean
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. R. S. Springell
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. C. Monney
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. K. J. Zhou
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. J. Pereiro
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. I. Božović
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. B. Dalla Piazza
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. H. M. Rønnow
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. E. Morenzoni
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. J. van den Brink
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. T. Schmitt
    View author publications

    You can also search for this author in PubMed Google Scholar

  12. J. P. Hill
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

Experiment: M.P.M.D., J.P.H., R.S.S., C.M., K.J.Z. and T.S.; sample growth: I.B.; sample characterization: I.B., M.P.M.D., J.P., R.S.S. and E.M.; two-magnon calculations: B.D.P. and H.M.R.; data analysis and interpretation: M.P.M.D., J.P.H., J.v.d.B., T.S., C.M., K.J.Z. and H.M.R.; project planning: J.P.H., M.P.M.D., T.S. and I.B.; paper writing: M.P.M.D. and J.P.H., with contributions from all authors.

Corresponding authors

Correspondence to M. P. M. Dean or J. P. Hill.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 779 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Dean, M., Springell, R., Monney, C. et al. Spin excitations in a single La2CuO4 layer. Nature Mater 11, 850–854 (2012). https://doi.org/10.1038/nmat3409

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nmat3409

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing