Thermal properties characterization of silicon and germanium nanostructures with molecular dynamics simulations

Thermoelectric materials have captured considerable attention of researchers due to their possible adaptation in power generation, energy conversion, and solid-state cooling applications. In this work, thermal transport properties of silicon and germanium elements which are good candidates for thermoelectric materials were analyzed via Green-Kubo method. Tersoff was used to define the interaction between atoms. Alloys and superlattice structures from silicon and germanium (SiGe) systems were chosen to examine. At room temperature, thermal transport properties in produced macro and nano size systems were calculated via equilibrium molecular dynamic method, then obtained results were compared regarding the size. Besides, the effects of tem- perature change, geometry, periodicity, crystal orientation, interface roughness and surface area of the SiGe based nano structures were investigated. As a conclusion of this thesis work, lattice thermal transport properties of SiGe based materials were computed and possible nano structures having high ther- moelectric performance were designated.