Abstract
Microscopic energy transport processes mediated by fundamental energy carriers, including phonons, electrons and spins, play an essential role in determining the performance of next-generation energy, electronic, and quantum materials. Despite significant recent progress in experimental and computational methods to probe and model these processes, fundamental challenges remain in our capability to predict and engineer energy transport properties of materials, especially when they are driven far away from thermal equilibrium. In this talk, I will discuss our recent experimental and computational efforts to understand microscopic energy transport processes in emerging technologically relevant materials. First, I will describe our development of a scanning ultrafast electron microscope (SUEM) that can directly image photoexcited nonequilibrium energy transport processes with combined high spatial and temporal resolutions, which are highly relevant for photovoltaic and optoelectronic applications. Second, I will discuss our recent understanding of the impact of nonequilibrium electron-phonon interaction on thermal, electrical and thermoelectric transport in semiconductors, with a particular focus on wide bandgap semiconductors for power electronics and 2D semiconductors. In particular, I will introduce a novel low-dissipation transport regime, coupled electron-phonon hydrodynamics, where electrons and phonons develop a collective drift velocity.
Biography
Bolin Liao is an associate professor and the vice department chair of mechanical engineering at UCSB. He received his Ph.D. in mechanical engineering from MIT in 2016 and was a Kavli prize postdoc fellow at Caltech from 2016 to 2017. His current research focuses on the fundamental understanding of microscopic energy transport mediated by phonons, electrons, and spins in emerging quantum, electronic, and energy materials and their potential applications in next-generation energy and microelectronic systems. His research has been recognized by an outstanding Ph.D. thesis award from MIT, a Kavli prize postdoctoral fellowship in nanoscience from Caltech, US Department of Energy Early Career Award, NSF CAREER award, NASA Early Career Faculty Award, and Young Investigator Awards from ONR, AFOSR, and ARO.
Anyone interested is welcome to attend.