Letter | Published:

Nonlinear inelastic electron scattering revealed by plasmon-enhanced electron energy-loss spectroscopy

Nature Physics volume 10, pages 753757 (2014) | Download Citation

Abstract

Electron energy-loss spectroscopy is a powerful tool for identifying the chemical composition of materials1,2,3,4,5. It relies mostly on the measurement of inelastic electrons, which carry specific atomic or molecular information. Inelastic electron scattering, however, has a very low intensity, often orders of magnitude weaker than that of elastically scattered electrons. Here, we report the observation of enhanced inelastic electron scattering from silver nanostructures, the intensity of which can reach up to 60% of its elastic counterpart. A home-made scanning probe electron energy-loss spectrometer6 was used to produce highly localized plasmonic excitations, significantly enhancing the strength of the local electric field of silver nanostructures. The intensity of inelastic electron scattering was found to increase nonlinearly with respect to the electric field generated by the tip–sample bias, providing direct evidence of nonlinear electron scattering processes.

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References

  1. 1.

    Low-energy EELS investigation of surface electronic excitations on metals. Surf. Sci. Rep. 22, 1–71 (1995).

  2. 2.

    et al. Element-selective single atom imaging. Science 290, 2280–2282 (2000).

  3. 3.

    et al. Spectroscopic imaging of single atoms within a bulk solid. Phys. Rev. Lett. 92, 95502 (2004).

  4. 4.

    et al. Element-selective imaging of atomic columns in a crystal using STEM and EELS. Nature 450, 702–704 (2007).

  5. 5.

    et al. Capturing the signature of single atoms with the tiny probe of a STEM. Ultramicroscopy 123, 80–89 (2012).

  6. 6.

    et al. Spatially resolved scanning probe electron energy spectroscopy for Ag islands on a graphite surface. Rev. Sci. Instrum. 80, 103705 (2009).

  7. 7.

    & Fast-electron spectroscopy of surface excitations. Phys. Rev. Lett. 26, 229–232 (1971).

  8. 8.

    Surface plasmon coupling in clusters of small spheres. Phys. Rev. Lett. 49, 936–940 (1982).

  9. 9.

    , , , & Reflection electron energy loss spectrum of surface plasmon excitation of Ag: A Monte Carlo study. Phys. Rev. B 66, 085411 (2002).

  10. 10.

    , & Surface plasmon dispersion on sputtered and nanostructured Ag (001). Phys. Rev. B 67, 045406 (2003).

  11. 11.

    et al. Mapping surface plasmons on a single metallic nanoparticle. Nature Phys. 3, 348–353 (2007).

  12. 12.

    , , , & Surface exciton polaritons in individual Au nanoparticles in the far-ultraviolet spectral regime. Phys. Rev. B 77, 245402 (2008).

  13. 13.

    et al. Electron energy-loss spectroscopy (EELS) of surface plasmons in single silver nanoparticles and dimers: Influence of beam damage and mapping of dark modes. ACS Nano 3, 3015–3022 (2009).

  14. 14.

    et al. Three-dimensional imaging of localized surface plasmon resonances of metal nanoparticles. Nature 502, 80–84 (2013).

  15. 15.

    , , & Scanning probe energy loss spectroscopy. Surf. Sci. 502–503, 224–231 (2002).

  16. 16.

    , & Surface plasmon excitation of Au and Ag in scanning probe energy loss spectroscopy. Appl. Phys. Lett. 93, 213109 (2008).

  17. 17.

    , & Photon-induced near-field electron microscopy. Nature 462, 902–906 (2009).

  18. 18.

    , & Photon-induced near-field electron microscopy (PINEM): Theoretical and experimental. New J. Phys. 12, 123028 (2010).

  19. 19.

    , & Subparticle ultrafast spectrum imaging in 4d electron microscopy. Science 335, 59–64 (2012).

  20. 20.

    et al. Probing the structure of single-molecule surface-enhanced Raman scattering hot spots. J. Am. Chem. Soc. 130, 12616–12617 (2008).

  21. 21.

    et al. Probing the electromagnetic field of a 15-nanometre hotspot by single molecule imaging. Nature 469, 385–388 (2011).

  22. 22.

    , , , & Nanoscale probing of adsorbed species by tip-enhanced Raman spectroscopy. Phys. Rev. Lett. 92, 096101 (2004).

  23. 23.

    , , & Scanning-probe Raman spectroscopy with single-molecule sensitivity. Phys. Rev. B 73, 193406 (2006).

  24. 24.

    , & Nano-optics from sensing to waveguiding. Nature Photon. 1, 641–648 (2007).

  25. 25.

    , & Plasmonics for near-field nano-imaging and superlensing. Nature Photon. 3, 388–394 (2009).

  26. 26.

    et al. Generation of molecular hot electroluminescence by resonant nanocavity plasmons. Nature Photon. 4, 50–54 (2010).

  27. 27.

    , & Density-matrix approach for the electroluminescence of molecules in a scanning tunneling microscope. Phys. Rev. Lett. 106, 177401 (2011).

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Acknowledgements

This work was partly supported by the National Basic Research Program of China (Grant Nos. 2010CB923301 and 2010CB923304), the National Science Foundation of China (Grant Nos. 10404026 and 20925311) and the MOE 211 project.

Author information

Affiliations

  1. Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China

    • Chun Kai Xu
    • , Wen Jie Liu
    • , Pan Ke Zhang
    • , Meng Li
    • , Han Jun Zhang
    • , Ke Zun Xu
    •  & Xiang Jun Chen
  2. Hefei National Lab for Physical Science at Microscale and Synergetic Innovation Center of Quantum Information Quantum Physics, University of Science and Technology of China, Hefei 230026, China

    • Chun Kai Xu
    • , Pan Ke Zhang
    • , Meng Li
    • , Yi Luo
    •  & Xiang Jun Chen
  3. Department of Theoretical Chemistry and Biology, Royal Institute of Technology, S-106 91 Stockholm, Sweden

    • Yi Luo

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Contributions

W.J.L. and P.K.Z. contributed equally to this work. X.J.C. and K.Z.X. initiated the study. C.K.X., Y.L. and X.J.C. supervised the project. C.K.X. and X.J.C. designed the experiments. W.J.L., P.K.Z., M.L. and H.J.Z. performed the experiments. C.K.X., W.J.L., P.K.Z. and X.J.C. analysed the data. Y.L. proposed the theoretical model. C.K.X., Y.L. and X.J.C. interpreted the experiments and wrote the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Yi Luo or Xiang Jun Chen.

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DOI

https://doi.org/10.1038/nphys3051

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