Design and commissioning of an aberration-corrected ultrafast spin-polarized low energy electron microscope with multiple electron sources

Weishi Wan; Lei Yu; Lin Zhu; Xiaodong Yang; Zheng Wei; Jefferson Zhe Liu; Jun Feng; Kai Kunze; Oliver Schaff; Ruud Tromp; Wen-Xin Tang

doi:10.1016/j.ultramic.2016.12.019

Design and commissioning of an aberration-corrected ultrafast spin-polarized low energy electron microscope with multiple electron sources

Ultramicroscopy. 2017 Mar:174:89-96. doi: 10.1016/j.ultramic.2016.12.019. Epub 2016 Dec 27.

Authors

Weishi Wan¹, Lei Yu², Lin Zhu², Xiaodong Yang², Zheng Wei², Jefferson Zhe Liu³, Jun Feng¹, Kai Kunze⁴, Oliver Schaff⁴, Ruud Tromp⁵, Wen-Xin Tang⁶

Affiliations

¹ College of Materials Science and Engineering, Chongqing University, Chongqing 400044, PR China; Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
² College of Materials Science and Engineering, Chongqing University, Chongqing 400044, PR China.
³ College of Materials Science and Engineering, Chongqing University, Chongqing 400044, PR China; Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
⁴ SPECS Surface Nano Analysis GmbH, Voltastrasse 5, 13355 Berlin, Germany.
⁵ IBM Research Division, T.J. Watson Research Center, Yorktown Heights, NY 10598, USA.
⁶ College of Materials Science and Engineering, Chongqing University, Chongqing 400044, PR China; School of Physics, Monash University, Clayton, VIC 3800, Australia. Electronic address: wenxintang@cqu.edu.cn.

PMID: 28063340
DOI: 10.1016/j.ultramic.2016.12.019

Abstract

We describe the design and commissioning of a novel aberration-corrected low energy electron microscope (AC-LEEM). A third magnetic prism array (MPA) is added to the standard AC-LEEM with two prism arrays, allowing the incorporation of an ultrafast spin-polarized electron source alongside the standard cold field emission electron source, without degrading spatial resolution. The high degree of symmetries of the AC-LEEM are utilized while we design the electron optics of the ultrafast spin-polarized electron source, so as to minimize the deleterious effect of time broadening, while maintaining full control of electron spin. A spatial resolution of 2nm and temporal resolution of 10ps (ps) are expected in the future time resolved aberration-corrected spin-polarized LEEM (TR-AC-SPLEEM). The commissioning of the three-prism AC-LEEM has been successfully finished with the cold field emission source, with a spatial resolution below 2nm.

Keywords: Aberration correction; LEEM; SPLEEM; STM.

Publication types

Research Support, Non-U.S. Gov't