Design of a mirror aberration corrector and a beam separator for LEEM

• Published in: Applied surface science 2009-11, Vol.256 (4), p.1035-1041
• Main Authors: Tsuno, K., Yasue, T., Koshikawa, T.
• Format: Article
• Language: English
• Subjects: Beam focusing and bending magnets, wiggler magnets, and quadrupoles; Beam optics; Chromatic and geometrical aberrations; Electromagnetism; electron and ion optics; Exact sciences and technology; Fundamental areas of phenomenology (including applications); LEEM, SPLEEM, Mirror corrector, Beam separator, Cathode lens; Physics
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2009.05.114

A SPLEEM (spin polarized low energy electron microscope) has been designed with a numerical simulation of electrostatic and magnetic field distributions and electron ray trajectories. Highly (more than 90%) spin polarized electron source has been used. A Wien type spin manipulator and a magnetic lens type spin rotator are used to align spin direction. A magnetic field free objective lens is designed to observe magnetic domain structure of magnetic materials. High or low magnification mode can be selected by using a combined electrostatic and magnetic objective lens for a high spatial resolution and a wide imaging area observation. An electrostatic mirror aberration corrector is installed after the image forming objective lens. A double deflection 45° beam separator is used to bend the direction of electrons from the source to the objective lens and from the objective lens to the mirror aberration corrector.