Title：Exploring Electronic Structure of Low Dimensional Quantum Materials             with Application to Graphene and Topological Quantum Materials

Invieted Speaker：Dr. Yulin Chen (陈宇林)

        Associate Professor & Fellow of Jesus College

        Physics Department, University of  Oxford, UK

Time：2015年6月23日（周二）上午10:00

Room：A717 Hall,College of Chemistry and Molecular Engineering 

Abstract：

Exploring the electronic properties of materials, including the spin polarization and dynamics is essential for understanding the underlying physics and their potential applications. Angle-resolved photoemission spectroscopy (ARPES) has been proved to be one of the most powerful tools in studying the electronic structure of solids. By directly observing band dispersions with momentum, spin and temporal resolution, ARPES can provide vital information connecting the electronic, magnetic, and chemical structures of solids.

With the swift development of material science and nanotechnology, the need for investigating electronics properties of matter with accurate local information naturally stems up. However, even with today’s state-of-the-art ARPES, this new requirements can hardly be addressed, as the spatial resolution of conventional ARPES is typically 0.1~1mm, which is incapable of studying many important subjects, including) novel mesoscopic (sub-micron to nano-scale) materials, ii) materials with phase separation iii) exotic low dimensional materials and iv) in-situ study of single functional device.

In such a context, developing a new type of ARPES with sub-micron spatial resolution, as well as ultra-high energy, momentum and spin resolution is urged to address the emerging need of materials’ research forefronts, which will also fill the gap between the atomic electronic information provided by the STM spectroscopy and the low-spatially resolved data supplied by classical ARPES and NEXAFS techniques.

In this talk, I will first introduce the basics of ARPES and its application to various novel quantum materials to demonstrate its power; then discuss our recent efforts in developing the specially resolved ARPES technique/instrument, and show some preliminary results, including the study on spatially inhomogeneous graphene and topological quantum materials.

Resume: 

Dr. Yulin Chen received his B.S. degree in physics from USTC in 2000, and obtained his Ph.D. in physics at Stanford University in 2008, working with Prof. Zhi-Xun Shen. After working as a postdoc(2008-2009), an associate staff scientist (2009-2010), and a staff scientist (2010-2011) at SLAC National Accelerator Laboratory, he joined the Department of Physics at Oxford University in 2012, as a University Lecturer & Fellow of Jesus College. Now he is an associate professor & Fellow of Jesus College at Oxford University. He is a recipient of Outstanding Young Researcher Award (MacronixPrize) from the International Organization of Chinese Physicists and Astronomers (2012) and a William E. and Diane M. Spicer Young Investigator Award from Stanford Synchrotron Radiation Light source (2009). His research interests lie in experimental condensed matter physics; and specifically, in understanding the behavior of electrons in unconventional materials, such as topological quantum matters and strongly correlated systems, by using ARPES.