Negative differential conductance and hot phonons in suspended nanotube molecular wires.
Freely suspended metallic single-walled carbon nanotubes (SWNTs) exhibit reduced current carrying ability compared to those lying on substrates, and striking negative differential conductance at low electric fields. Theoretical analysis reveals significant self-heating effects including electron scattering by hot nonequilibrium optical phonons. Electron transport characteristics under strong self-heating are exploited for the first time to probe the thermal conductivity of individual SWNTs (approximately 3600 W m-1 K-1 at T=300 K) up to approximately 700 K, and reveal a 1/T dependence expected for umklapp phonon scattering at high temperatures.
Pop
Eric
E
Department of Chemistry and Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA.
Mann
David
D
Cao
Jien
J
Wang
Qian
Q
Goodson
Kenneth
K
Dai
Hongjie
H