A Highly Scalable Simulation Model for Atomistic Calculation of Thermal Properties of Silicon

A portable parallel program developed for molecular dynamics simulations shows excellent scalability on a variety of architectures including IBM’s BlueGene, IBM’s Power4 P655+, and Linux clusters. A task that would have taken 30 days on a single processor can now be completed in 2.5,5 hours on 1024 Power4+ processors and 1728 BlueGene’s PowerPC processors respectively, using our parallel molecular dynamics algorithm. This program computes the thermal conductivity of bulk silicon. In particular, we investigate how computational domain size (number of atoms) affects the predicted accuracy. We also explore the thermal conductivity of thin film silicon at room temperature. Results show that, as the thickness increases up to 300 nm, the thermal conductivity approaches the bulk thermal conductivity. This work permits us to confidently apply molecular dynamics to the simulation of thermal conductivity of both bulk materials and thin films.