Abstract

The conduction of heat is one of the fundamental energy transport mechanisms in nature. Traditionally, the phenomenon of heat conduction is believed to follow Fourier’s law, which has received great success in describing macroscopic heat transport and is widely accepted as a general truth. Here the speaker will demonstrate that phonons transport in one-dimensional nanomaterials super diffusively, which leads to a size dependent thermal conductivity. In other words, Fourier’s law is not applicable in nano materials. Moreover, using silicon nanowire as example, different mechanisms to reduce thermal conductivity by phononic engineering will be presented. All these features combined together to make semiconducting nanowire a very promising candidate for thermoelectric device applications. Subsequently, the speaker will present their recent theoretical approach for modeling phonon transport in two-dimensional materials and nanoscale interfacial thermal transport.

About the Speaker

Dr. Zhang Gang received B. Sci & PhD in physics from Tsinghua University in 1998 & 2002, respectively. Dr. Zhang is currently a senior scientist & capability group manager in Institute of High Performance Computing (IHPC), A*STAR, Singapore, which he joined in February 2013. Prior to his joining IHPC, he was a professor at Department of Electronics, Peking University. His research is focused on the energy transfer & harvesting in nanostructured materials. He has authored or co-authored more than 160 publications in the peer-reviewed international journals, including 26 published in prestigious journals with impact factor higher than 10, & 9 review articles including 1 in Review of Modern Physics. His H-index is 41 & total citation is more than 6000. He was awarded with an Outstanding Ph.D. thesis Award in Tsinghua University (2002) & Singapore Millennium Foundation Fellowship (2002-2004). His research achievements are also matched with competency in teaching. Three students under his supervision have received the Chinese Government Award for Outstanding Students Studying Abroad.