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Breakdown of the adiabatic Born–Oppenheimer approximation in graphene

Abstract

The adiabatic Born–Oppenheimer approximation (ABO) has been the standard ansatz to describe the interaction between electrons and nuclei since the early days of quantum mechanics1,2. ABO assumes that the lighter electrons adjust adiabatically to the motion of the heavier nuclei, remaining at any time in their instantaneous ground state. ABO is well justified when the energy gap between ground and excited electronic states is larger than the energy scale of the nuclear motion. In metals, the gap is zero and phenomena beyond ABO (such as phonon-mediated superconductivity or phonon-induced renormalization of the electronic properties) occur3. The use of ABO to describe lattice motion in metals is, therefore, questionable4,5. In spite of this, ABO has proved effective for the accurate determination of chemical reactions6, molecular dynamics7,8 and phonon frequencies9,10,11 in a wide range of metallic systems. Here, we show that ABO fails in graphene. Graphene, recently discovered in the free state12,13, is a zero-bandgap semiconductor14 that becomes a metal if the Fermi energy is tuned applying a gate voltage13,15, Vg. This induces a stiffening of the Raman G peak that cannot be described within ABO.

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Figure 1: Experimental set-up.
Figure 2: Raman G peak of doped graphene.
Figure 3: Schematic π band structure of doped graphene near the high-symmetry K point of the Brillouin zone.

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References

  1. Born, M. & Oppenheimer, J. R. Zur quantentheorie der molekeln. Ann. Phys. 84, 457–484 (1927).

    Article  CAS  Google Scholar 

  2. Ziman, J. M. Electrons and Phonons (Oxford Univ. Press, Oxford, 1960).

    Google Scholar 

  3. Grimvall, G. The Electron-Phonon Interaction in Metals (North-Holland, Amsterdam, 1981).

    Google Scholar 

  4. Ponosov, Y. S., Bolotin, G. A., Thomsen, C. & Cardona, M. Raman scattering in Os: Nonadiabatic renormalization of the optical phonon self energies. Phys. Status Solidi B 208, 257–269 (1988).

    Article  Google Scholar 

  5. White, J. D., Chen, J., Matsiev, D., Auerbach, D. J. & Wodtke, A. M. Conversion of large-amplitude vibration to electron excitation at a metal surface. Nature 433, 503–505 (2005).

    Article  CAS  Google Scholar 

  6. Kroes, G. J., Gross, A., Baerends, E. J., Scheffler, M. & McCormack, D. A. Quantum theory of dissociative chemisorption on metal surfaces. Acc. Chem. Res. 35, 193–200 (2002).

    Article  CAS  Google Scholar 

  7. Alfe, D., Gillan, M. J. & Price, G. D. The melting curve of iron at the pressures of the Earth’s core from ab initio calculations. Nature 401, 462–464 (1999).

    Article  CAS  Google Scholar 

  8. Walker, B. G., Molteni, C. & Marzari, N. Ab initio molecular dynamics of metal surfaces. J. Phys. Condens. Matter 16, S2575–S2596 (2004).

    Article  CAS  Google Scholar 

  9. Chester, G. V. The theory of interaction of electrons with lattice vibrations in metals. Adv. Phys. 10, 357–400 (1961).

    Article  CAS  Google Scholar 

  10. Baroni, S., De Gironcoli, S., Dal Corso, A. & Giannozzi, P. Phonons and related crystal properties from density functional perturbation theory. Rev. Mod. Phys. 73, 515–562 (2001).

    Article  CAS  Google Scholar 

  11. Savrasov, S. Y. & Savrasov, D. Y. Electron-phonon interactions and related physical properties of metals from linear-response theory. Phys. Rev. B 54, 16487–16501 (1996).

    Article  CAS  Google Scholar 

  12. Novoselov, K. S. et al. Two dimensional atomic crystals. Proc. Natl Acad. Sci. USA 102, 10451–10453 (2005).

    Article  CAS  Google Scholar 

  13. Novoselov, K. S. et al. Electric field effect in atomically thin carbon films. Science 306, 666–669 (2004).

    Article  CAS  Google Scholar 

  14. Wallace, P. R. The band theory of graphite. Phys. Rev. 71, 622–634 (1947).

    Article  CAS  Google Scholar 

  15. Novoselov, K. S. et al. Two dimensional gas of massless Dirac fermions in graphene. Nature 438, 197–200 (2005).

    Article  CAS  Google Scholar 

  16. Zhang, Y., Tan, Y. W., Stormer, H. L. & Kim, P. Experimental observation of the quantum Hall effect and Berry’s phase in graphene. Nature 438, 201–204 (2005).

    Article  CAS  Google Scholar 

  17. Ferrari, A. C. et al. Raman spectrum of graphene and graphene layers. Phys. Rev. Lett. 97, 187401 (2006).

    Article  CAS  Google Scholar 

  18. Yan, J., Zhang, Y., Kim, P. & Pinczuk, A. Electric field effect tuning of electron-phonon coupling in graphene. Preprint at <http://www.arxiv.org/cond-mat/0612634> (2006).

  19. Tuinstra, F. & Koenig, J. Raman spectrum of graphite. J. Chem. Phys. 53, 1126–1130 (1970).

    Article  CAS  Google Scholar 

  20. Piscanec, S., Lazzeri, M., Mauri, F., Ferrari, A. C. & Robertson, J. Kohn anomalies and electron phonon interactions in graphite. Phys. Rev. Lett. 93, 185503 (2004).

    Article  CAS  Google Scholar 

  21. Dubay, O. & Kresse, G. Accurate density functional calculations for the phonon dispersion relations of graphite layer and carbon nanotubes. Phys. Rev. B 67, 035401 (2003).

    Article  Google Scholar 

  22. Lazzeri, M., Piscanec, S., Mauri, F., Ferrari, A. C. & Robertson, J. Phonon linewidths and electron-phonon coupling in graphite and nanotubes. Phys. Rev. B 73, 155426 (2006).

    Article  Google Scholar 

  23. Zhang, Y. et al. Landau-level splitting in graphene in high magnetic fields. Phys. Rev. Lett. 96, 136806 (2006).

    Article  CAS  Google Scholar 

  24. Moos, G., Gahl, C., Fasel, R., Wolf, M. & Hertel, T. Anisotropy of quasiparticle lifetimes and the role of disorder in graphite from ultrafast time-resolved photoemission spectroscopy. Phys. Rev. Lett. 87, 267402 (2001).

    Article  CAS  Google Scholar 

  25. Kampfrath, T., Perfetti, L., Schapper, F., Frischkorn, C. & Wolf, M. Strongly coupled optical phonons in the ultrafast dynamics of electronic energy and current relaxation in graphite. Phys. Rev. Lett. 95, 187403 (2005).

    Article  Google Scholar 

  26. Lazzeri, M. & Mauri, F. Non-adiabatic Kohn-anomaly in a doped graphene monolayer. Phys. Rev. Lett. 97, 266407 (2006).

    Article  Google Scholar 

  27. Ando, T. Anomaly of optical phonon in monolayer graphene. J. Phys. Soc. Jpn. 75, 124701 (2006).

    Article  Google Scholar 

  28. Castro Neto, A. H. & Guinea, F. Electron-phonon coupling and Raman spectroscopy in graphene. Phys. Rev. B 75, 045404 (2007).

    Article  Google Scholar 

  29. Ashcroft, N. W. & Mermin, N. D. Solid State Physics (Saunders College, London, 1976).

    Google Scholar 

  30. Piscanec, S., Lazzeri, M., Robertson, J., Ferrari, A. C. & Mauri, F. Optical phonons in carbon nanotubes: Kohn anomalies, peierls distortions and dynamic effects. Phys. Rev. B 75, 035427 (2007).

    Article  Google Scholar 

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Acknowledgements

The authors thank P. Kim and A. Pinczuk for useful discussions and for sending us a preprint of ref. 18. A.C.F. acknowledges funding from the Royal Society and The Leverhulme Trust. The calculations were carried out at IDRIS (Orsay).

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Correspondence to Andrea C. Ferrari or Francesco Mauri.

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Pisana, S., Lazzeri, M., Casiraghi, C. et al. Breakdown of the adiabatic Born–Oppenheimer approximation in graphene. Nature Mater 6, 198–201 (2007). https://doi.org/10.1038/nmat1846

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