First-principles method is a powerful approach to study atomic scale physics and deals with fundamental physical processes. With its introduction into thermal transport area, the quantum description of quantized lattice vibrations, phonons, achieved great success in predicting/explaining thermal transport properties in the past two decades. However, frontier technologies based on solid-state systems and devices will soon meet the boundary of our usual understanding of energy transport. Our pursuit of faster computing, higher energy efficiency and better sustainability requires major advancements in the study of quantum energy transport. Our research on phonon dynamics and thermal transport then has both technological and scientific importance that could lead to discovery of novel transport phenomena and disruptive technology strategies.
My PhD research is motivated by the following challenges in our community:
My research aims to tackle the challenges above along these directions:
Nonequilibrium carrier transport
High temperature thermal transport
Temperature-dependent optical responses
[Sustained community software: FourPhonon](https://zrhan.notion.site/Sustained-community-software-FourPhonon-4d813e9773774925bc83d7ac4cd56214)
Two-dimensional (2D) semiconductors are emerging candidates for nanoscale transistors, because ultrathin 2D channels can reduce short channel effects and have reasonable mobility at sub-nanometer (atomic) thickness. Pushing 2D transistors into commercial adoptions is a grand challenge for device community.
Graphene has been studied as an emerging atomically thin electronic and optoelectronic material and for thermal management. As a longstanding question and despite extensive theoretical and experimental studies, its thermal transport is still poorly understood and many aspects remain inconclusive. In this two-phase study, we begin with optical phonon dynamics before extending our methodology to the full phonon spectrum: