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Acknowledgements
metals (see, for example, Table 1.3 of ref. 29). Note that the
The authors thank P. Kim and A. Pinczuk for useful discussions and for sending us a preprint of
stronger the electron phonon coupling with q = 0 phonons, the
ref. 18. A.C.F. acknowledges funding from the Royal Society and The Leverhulme Trust. The
calculations were carried out at IDRIS (Orsay).
larger the difference between ABO and non-ABO frequencies.
Correspondence and requests for materials should be addressed to A.C.F or F.M.
However, the lattice dynamics is well described by ABO if the
Supplementary Information accompanies this paper on www.nature.com/naturematerials.
electron phonon coupling with q = 0 phonons is so strong that
Competing financial interests
the electron-momentum relaxation is faster than the lattice motion.
The authors declare that they have no competing financial interests.
We anticipate that the ABO breakdown described here will
affect the vibrational properties of carbon nanotubes30 and Reprints and permission information is available online at http://npg.nature.com/reprintsandpermissions/
nature materials VOL 6 MARCH 2007 www.nature.com/naturematerials 201 [ Pobierz całość w formacie PDF ]