2005/09/05 by Jian Wang, Jian‐Sheng Wang, Wang, Jian +2
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Mechanical and Optical Resonators #Statistical Mechanics (cond-mat.stat-mech) #Thermal Radiation and Cooling Technologies #Thermal properties of materials #cond-mat.stat-mech
paper · pdf · doi:10.48550/arxiv.cond-mat/0509092
10 pages 8 figures
arxiv created 2005/09/05 · openalex publication_date 2005/09/05 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We derive expression for energy flux in terms of lattice normal mode coordinates. Energy transmission across solid junctions from lattice dynamic point of view is given and its relation with atomic masses, lattice constants, and group velocities is clarified. A scattering boundary method (SBM) is proposed for calculating the amplitude transmission across solid junctions. The phonon transmission coefficients and thermal conductance are calculated for two kinds of acoustically mismatched junctions: different chirality nanotubes (11,0) to (8,0), and Si-Ge interface structure. Our calculation shows a mode-dependent transmission in nanotube junction due to the high symmetry vibrating motions for nanotube atoms, indicating its possible important role in nanotube mixture thermal conductance. Energy transmission and Kapitza conductance across the Si-Ge interface [001] are calculated for the Si-Ge diamond-type structure. It is shown that the energy transmission across the Si-Ge interface depends on the incident angle and on the interface mode conversion. A critical incident angle about 42 degrees numerically found for waves incident from Ge to Si. Our numerical result of the Kapitza conductance at temperature T=200K is GK=4.6x108 W/(Km2) We find numerically scaling law GK proportional to T2.87 for [001] interface at low temperature.