Heat Dissipation Mechanism at Carbon Nanotube Junctions on Silicon Oxide Substrate
L Chen and S Kumar, JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME, 136, 052401 (2014).
This study investigates heat dissipation at carbon nanotube (CNT) junctions supported on silicon dioxide substrate using molecular dynamics simulations. The temperature rise in a CNT (similar to top CNT) not making direct contact with the oxide substrate but only supported by other CNTs (similar to bottom CNT) is observed to be hundreds of degree higher compared with the CNTs well-contacted with the substrate at similar power densities. The analysis of spectral temperature decay of CNT-oxide system shows very fast intratube energy transfer in a CNT from high-frequency band to intermediate-frequency bands. The low frequency phonon band (0-5 THz) of top CNT shows two-stage energy relaxation which results from the efficient coupling of low frequency phonons in the CNT- oxide system and the blocking of direct transport of high- and intermediate-frequency phonons of top CNT to the oxide substrate by bottom CNT.
Return to Publications page