Further decrease of the thermal conductivity of superlattice through embedding nanoparticle

Abstract

Utilizing different nanostructures can effectively control phonons transport of their corresponding macrostructures, and this will contribute to the development of thermoelectric energy harvesting and microelectronic thermal management. This work tends to decrease the thermal conductivity (TC) of Si/Ge superlattices (SLs) by embedding germanium nanoparticles (GNPs). The thermal transport property in such structure was investigated by non-equilibrium molecular dynamics (NEMD) method. Results showed that embedding NPs can significantly reduce the TC of SLs, but only when the particle number is less than half of the SL's periods, above which the reduction effect will be greatly decreased. In addition, we also investigated the effects of temperature, system length, particle size and number on the TC. The thermal transport properties of the system are deeply revealed by calculating and analyzing phonons parameters such as density of states, participation ratio, mean free paths (MFPs) and spectral heat flow.