Department of Mechanical Engineering
Stanford University
Principal Investigator
Kenneth E. Goodson
Negative Differential Conductance and Hot Phonons in Suspended Nanotube Molecular Wires
Pop, E., Mann, D., Cao, J., Wang, Q., Goodson, K.E., and Dai, H., 2005, "Negative Differential Conductance and Hot Phonons in Suspended Nanotube Molecular Wires," Physical Review Letters, Vol. 95, pp. 155505-155509.
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 (~3600 Wm-1 K-1 at T=300 K) up to ~700 K, and reveal a 1/T dependence expected for umklapp phonon scattering at high temperatures.
Related Projects
Carbon nanotubes offer unusual thermal, mechanical, and electrical properties, which vary with chirality, geometry (multiwall vs single-wall), and length. They are promising for a variety of...
Thermal interface materials (TIMs) play a central role in the performance and reliability of electronic systems. They are the route for thermal conduction between semiconductor chips and metal heat...
Hotspot mitigation, thermal management paths, and thermomechanical degradation are key challenges for 3D integration, in particular due to the increased quantity and complexity of "thermally...