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arXiv · 1308.1173

Electron temperature dependence of the electron-phonon coupling strength in double-wall carbon nanotubes

Ioannis Chatzakis
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Abstract

We applied Time-Resolved Two-Photon Photoemission spectroscopy to probe the electron- phonon (e-ph) coupling strength in double-wall carbon nanotubes. The e-ph energy transfer rate G(Te,Tl) from the electronic system to the lattice depends linearly on the electron (Te) and lattice (Tl) temperatures for Te>ΘDebye. Moreover, we numerically solved the Two-Temperature Model. We found: (i) a Te decay with a 3.5 ps time constant and no significant change in Tl; (ii) an e-ph coupling factor of 2x10^16 W/m3; (iii) a mass-enhancement parameter, λ, of (5.4=+/- 0.9)x10e-4; and (iv) a decay time of the electron energy density to the lattice of 1.34+/-0.85 ps.

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Ioannis Chatzakis. 2013-08-06. Electron temperature dependence of the electron-phonon coupling strength in double-wall carbon nanotubes. https://doi.org/10.1063/1.4816055

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