Heat conduction in low-dimensional structures

Summary form only given, as follows: Understanding phonon heat conduction mechanisms in low-dimensional structures is of great interest for thermoelectric and microelectronic applications. In this paper, we discuss modeling and experimental results for heat conduction in 2-D and 1-D systems. For 2-D systems, models based on solving the phonon Boltzmann transport equation are developed for heat conduction in both the in-plane and the cross-plane directions of GaAs/AlAs and Si/Si_x Ge_1-x superlattices. Different interface scattering mechanisms are considered, including elastic vs. inelastic, and diffuse vs. specular. A comparison of the modeling and experimental results shows that the effective thermal conductivity of superlattices is controlled by interface scattering of phonons. Inelastic phonon scattering occurs at the interfaces. Modeling results based on partially diffuse and partially specular interfaces are in reasonable agreement with experimental data