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Experimental realization of suspended atomic chains composed of different atomic species


Research into nanostructured materials frequently relates to pure substances. This contrasts with industrial applications, where chemical doping or alloying is often used to enhance the electrical or mechanical properties of materials1. However, the controlled preparation of doped nanomaterials has been much more difficult than expected because the increased surface-area-to-volume ratio can, for instance, lead to the expulsion of impurities (self-purification)2. For nanostructured alloys, the influence of growth methods and the atomic structure on self-purification is still open to investigation2,3. Here, we explore, experimentally and with molecular dynamics simulations, to what extent alloying persists in the limit that a binary metal is mechanically stretched to a linear chain of atoms. Our results reveal a gradual evolution of the arrangement of the different atomic elements in the narrowest region of the chain, where impurities may be expelled to the surface or enclosed during elongation.

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Figure 1: Atom-resolved HRTEM snapshots of rod-like [110] Au1−xAgx NWs.
Figure 2: Atom-resolved HRTEM snapshots of suspended atomic chains.
Figure 3: Molecular dynamic simulations of Au concentration as a function of time in a Au0.6Ag0.4 wire as it is stretched.
Figure 4: Comparison between experimental and simulated HRTEM images of a mixed linear atomic chain.


  1. Callister, W. D. Jr. Materials Science and Engineering, an Introduction 5th edn (John Wiley & Sons, New York, 1999).

  2. Erwin, S. C. et al. Doping semiconductor nanocrystals. Nature 436, 91–94 (2005).

    Article  CAS  Google Scholar 

  3. Agraït, N., Yeyati, A. L. & van Ruitenbeek, J. M. Quantum properties of atomic-sized conductors. Phys. Rep. 377 (2–3), 81–279 (2003).

    Article  Google Scholar 

  4. Jarvis, S. P., Lantz, M. A., Ogiso, H., Tokumoto, H. & Dürig, U. Conduction and mechanical properties of atomic scale gold contacts Appl. Phys. Lett. 75, 3132–3134 (1999).

    Article  CAS  Google Scholar 

  5. Rodrigues, V., Fuhrer, T. & Ugarte, D. Signature of atomic structure in the quantum conductance of gold nanowire. Phys. Rev. Lett. 85, 4124–4127 (2000).

    Article  CAS  Google Scholar 

  6. Tosatti, E. Nanowire formation at metal–metal contacts. Sol. St. Commun. 135 (9–10), 610–617 (2005).

    Article  CAS  Google Scholar 

  7. Enomoto, D. A., Kurokawa, S. & Sakai, A. Quantized conductance in Au–Pd and Au–Ag alloy nanocontacts. Phys. Rev. B 65, 125410 (2002).

    Article  Google Scholar 

  8. Bakker, D. J., Noat, Y., Yanson, A. I. & van Ruitenbeek, J. M. Effect of disorder on the conductance of a Cu atomic point contact. Phys. Rev. B 65, 235416 (2002).

    Article  Google Scholar 

  9. Heesemskerk, J. W. T. et al. Current-induced transition in atomic-sized contacts of metallic alloys. Phys. Rev. B 67, 115416 (2003).

    Article  Google Scholar 

  10. Geng, W. T. & Kim, K. S. Linear monatomic wires stabilized by alloying: Ab initio density functional calculations. Phys. Rev. B 67, 233403 (2003).

    Article  Google Scholar 

  11. Fujii, A., Ochi, R., Kurokawa, S. & Sakai, A. Alloying effects on the 1G(0) contact of Au. Appl. Surf. Sci. 228, 207–212 (2004).

    Article  CAS  Google Scholar 

  12. Asaduzzaman, A. M. & Springborg, M. Structural and electronic properties of Au, Pt, and their bimetallic nanowires. Phys. Rev. B 72, 165422 (2005).

    Article  Google Scholar 

  13. Ohnishi, H., Kondo, Y. & Takayanagi, K. Quantized conductance through individual rows of suspended gold atoms. Nature 395, 780–783 (1998).

    Article  CAS  Google Scholar 

  14. Yanson, A. I., Bollinger, G. R., van den Brom, H. E., Agraït, N. & van Ruitenbeek, J. M. Formation and manipulation of a metallic wire of single gold atoms. Nature 395, 783–785 (1998).

    Article  CAS  Google Scholar 

  15. Rodrigues, V., Bettini, J. & Ugarte, D. Evidence for spontaneous spin-polarized transport in magnetic nanowires. Phys. Rev. Lett. 91, 096801 (2003).

    Article  Google Scholar 

  16. Delin, A., Tosatti, E. & Weht, R. Magnetism in atomic-size palladium contacts and nanowires. Phys. Rev. Lett. 92, 057201 (2004).

    Article  CAS  Google Scholar 

  17. Delin, A. & Tosatti, E. Magnetic phenomena in 5d transition metal nanowires. Phys. Rev. B 68, 144434 (2003).

    Article  Google Scholar 

  18. Thijssen, W. H. A., Marjenburgh, D., Bremmer, R. H. & van Ruitenbeek, J. M. Oxygen-enhanced atomic chain formation. Phys. Rev. Lett. 96, 026806 (2006).

    Article  CAS  Google Scholar 

  19. Kondo, Y. & Takayanagi, K. Synthesis and characterization of helical multi-shell gold nanowires. Science 289, 606–608 (2000).

    Article  CAS  Google Scholar 

  20. Rodrigues, V., Bettini, J., Rocha, A. R., Rego, L. G. C. & Ugarte, D. Quantum conductance in silver nanowires: Correlation between atomic structure and transport properties. Phys. Rev. B 65, 153402 (2002).

    Article  Google Scholar 

  21. Bettini, J., Rodrigues, V., González, J. C. & Ugarte, D. Real-time atomic resolution study of metal nanowires. Appl. Phys. A 81, 1513–1518 (2005).

    Article  CAS  Google Scholar 

  22. Smit, R. H. M., Untiedt, C., Yanson, A. I. & van Ruitenbeek, J. M. Common origin for surface reconstruction and the formation of chains of metal atoms. Phys. Rev. Lett. 87, 266102 (2001).

    Article  CAS  Google Scholar 

  23. Kondo, Y. & Takayanagi, K. Gold nanobridge stabilized by surface structure. Phys. Rev. Lett. 87, 266102 (2001).

    Article  Google Scholar 

  24. Williams, D. B. & Carter, C. B. Transmission Electron Microscopy (Plenum, New York, 1996).

  25. Stadelmann, P. EMS — a software package for electron diffraction analysis and HREM image simulation in materials science. Ultramicroscopy 21, 131 (1987).

    Article  CAS  Google Scholar 

  26. Cleri, F. & Rosato, V. Tight-binding potentials for transition metals and alloys. Phys. Rev. B 48, 22–33 (1993).

    Article  CAS  Google Scholar 

  27. Tománek, D., Aligia, A. A. & Balseiro, C. A. Calculation of elastic strain and electronic effects on surface segregation. Phys. Rev. B 32, 5051–5056 (1985).

    Article  Google Scholar 

  28. Coura, P. Z. et al. On the structural and stability features of linear atomic suspended chains formed from gold nanowires stretching. Nano Lett. 4, 1187–1191 (2004).

    Article  CAS  Google Scholar 

  29. Sato, F. et al. Computer simulations of gold nanowire formation: the role of outlayer atoms. Appl. Phys. A 81, 1527 (2005).

    Article  CAS  Google Scholar 

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This work was supported by LNLS, CNPq, FAPESP, FAPEMIG, IMMP/MCT, IN/MCT and CAPES. The authors acknowledge the invaluable help of the LNLS staff, in particular P. C. Silva for sample preparation.

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Correspondence to D. S. Galvão.

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Bettini, J., Sato, F., Coura, P. et al. Experimental realization of suspended atomic chains composed of different atomic species. Nature Nanotech 1, 182–185 (2006).

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