Manifestation of Kohn anomaly in 1/f fluctuations in metallic carbon nanotubes.
نویسندگان
چکیده
Low-frequency noise in metallic single walled carbon nanotubes is shown to be strongly dependent on the Fermi level position and the applied electric field across the nanotube. Resonance-like enhancement observed near optical phonon energy only when the Fermi level lies near the Dirac point is correlated to Raman G-band softening and broadening. The results suggest that the competition between zone-center and zone-boundary phonon scattering is the underlying origin of the large enhancement and resonance-like behavior of 1/f noise.
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ورودعنوان ژورنال:
- Physical review letters
دوره 103 21 شماره
صفحات -
تاریخ انتشار 2009