Presented By: CM-AMO Seminars
CM-AMO Seminar | New Progress in 2D Semiconductor van der Waals Heterostructures
Xiaodong Xu (University of Washington)
Abstract: Two-dimensional materials, with their wide range of physical properties, have emerged as an exciting platform for studying new physical phenomena. In particular, the ability to fabricate heterostructures between different 2D materials allows for designer condensed matter systems. In this talk, I will discuss our latest experimental progress on three different types of van der Waals heterostructures. I will first talk about interlayer excitons in semiconductor heterobilayers, which are analogous to spatially indirect excitons in double quantum wells, but with additional valley pseudospin properties. I will then discuss interlayer electron-phonon interactions in heterostructures formed by monolayer WSe¬2 and atomically thin boron nitride, in which a Raman silent phonon in boron nitride is activated by resonantly coupling to the electronic states in WSe2. Finally, I will conclude with a discussion of heterostructures formed by a monolayer semiconductor and a layered ferromagnetic semiconductor, a new system for controlling spin and pseudospin in 2D semiconductors by magnetic proximity effect.
Bio: Xiaodong Xu is a Boeing Distinguished Associate Professor in the Department of Physics and the Department of Materials Science and Engineering at the University of Washington. He received his PhD (Physics, 2008) from the University of Michigan and then performed postdoctoral research (2009-2010) at the Center for Nanoscale Systems at Cornell University. His nanoscale optoelectronics group at University of Washington focuses on creation, control, and understanding of novel device physics based on two-dimensional quantum materials. Selected awards include DAPRA YFA, NSF Early Career Award, DoE Early Career Award, Cottrell Scholar Award, University of Washington Innovation Award, and IUPAP Young Scientist Prize in Semiconductor Physics.
Bio: Xiaodong Xu is a Boeing Distinguished Associate Professor in the Department of Physics and the Department of Materials Science and Engineering at the University of Washington. He received his PhD (Physics, 2008) from the University of Michigan and then performed postdoctoral research (2009-2010) at the Center for Nanoscale Systems at Cornell University. His nanoscale optoelectronics group at University of Washington focuses on creation, control, and understanding of novel device physics based on two-dimensional quantum materials. Selected awards include DAPRA YFA, NSF Early Career Award, DoE Early Career Award, Cottrell Scholar Award, University of Washington Innovation Award, and IUPAP Young Scientist Prize in Semiconductor Physics.