Theory and modeling of electro-thermal transport in nanoscale materials and devices

Semiconductor electronics has shaped our world. The downscaling of device dimensions that made this possible not only presented enormous technological challenges, it also raised many fundamental questions. Over time a deep understanding of electron transport at the nanoscale has been developed, along with the computational tools to accurately capture the relevant physics. Electron transport cannot, in principle, be separated from phonon (thermal) transport. The physics of coupled electron-phonon transport is responsible for self-heating in nanoscale devices, which critically limits their performance and reliability, and for providing a route for enhanced thermoelectric energy conversion in nanostructures. These and other challenges have far-reaching implications for energy and 21st century electronics. Further progress will require a deeper understanding of thermal transport at the nanoscale, along with the development of new computational tools that treat electrons and phonons on equal footing, address challenges from the nano- to macro-scale, and that are tightly connected to predictive first principles materials modeling.

The mission of this research program is to advance the science and engineering of electro-thermal transport in nanoscale materials and devices, through innovative theory and modeling. Specific research thrusts include: 1) Investigating out-of-equilibrium electron-phonon transport/interaction at the nanoscale, such as self-heating in nanodevices, phonon transport on the nanoscale, and non-linear thermoelectric conversion. 2) Exploring 2D materials and devices with unique properties beyond the scope of traditional materials. 3) Developing state-of-the-art ab initio quantum theoretical modeling that predicts the electro-thermal transport characteristics of materials and devices, spans the atoms-to-devices hierarchy, and addresses a broader class of problems beyond the scope of current techniques.

This program will provide insights into the physics of coupled electron-phonon transport, where nonequilibrium phenomena on the nanoscale can arise. The development of innovative first principles multi-physics simulation tools will help explore emerging materials and devices, explain experiments, and accelerate innovation. Our research findings will address important challenges, enabling higher-performance and lower-power electronics, advanced thermoelectrics for efficient energy harvesting and solid-state cooling, and emerging applications for 2D materials. This program will benefit technologies used in the electronics, energy, communications, automotive and aerospace industries, where the interplay between electrons and phonons is important.