On the modeling of lattice thermal conductivity in semiconductor quantum dot superlattices

Abstract

We present a theoretical model for the cross-plane lattice thermal conductivity calculations in semiconductor quantum dot superlattices. Based on continuum approximation, our model takes into account scattering of acoustic phonons on quantum dots. In most practical cases, the dot volume fraction is relatively small and/or dot and host materials have a small acoustic mismatch. This fact lets us take into account only first order scattering events and to significantly simplify the calculations. The results of numerical simulations carried out for Si/Ge quantum dot superlattices show good agreement with experimental data. The proposed model is useful for many applications recently suggested for semiconductor quantum-dot superlattices.