报告题目：The New Aberration-Corrected LEEM/PEEM and its future applications in low dimensional system

报 告 人：唐文新，重庆大学

报告时间：2014年11月25日16:15

报告地点：理科楼B406

报告摘要：In this talk, I will introduce the basic functions of the low energy electron microscopy (LEEM) setup and discuss applications for semiconductor surface quantum structures formation study based on advanced capacities of LEEM.

Currently, we have procured a state-of-the-art aberration-corrected low energy electron microscopy/photoemission electron microscopy (AC-LEEM/PEEM+ high temperature STM) from SPECS, which has reached the spatial resolution of 1.7 nm. The main feature of this microscope is that it contains 3 prism arrays, as oppose to 2 in their standard configuration, allowing the possibility of adding a second electron gun to the system. Multiply MBE sources and gas sources were designed to facilitate in-situ real-time and real space imaging of technologically important interfaces and quantum structures formation under various conditions and high temperature up to 1200 0C. The high resolution AC-LEEM/PEEM+STM platform will be used to directly visualize and thereby understand some of key details of the semiconductor surface which are often different from those of bulk counterparts and the knowledge will be critical for advanced applications. To that end, we are currently developing an ultrafast spin-polarized electron gun in my lab, together with the necessary lenses, the future electron gun will realize time resolved spin-polarize LEEM (TR-SPLEEM). In this talk, I will discuss the design of this setup and microscope operation. The concept of TR-SPLEEM will be introduced briefly.