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| Publications [#249385] of Ying Wu
Papers Published
- Wu, YK; Robin, DS; Forest, E; Schlueter, R; Anders, S; Feng, J; Padmore, H; Wei, DH, Design and analysis of beam separator magnets for third generation aberration compensated PEEMs,
Nuclear Instruments and Methods in Physics Research A, vol. 519 no. 1-2
(2004),
pp. 230-241, Elsevier BV, ISSN 0168-9002 [doi]
(last updated on 2026/01/13)
Abstract:
A state of the art X-ray photoemission
electron microscope
(PEEM2) is operational at the Advanced Light
Source at a
resolution of typically 50 nm for a range of
chemical and
magnetic surface studies. A new microscope,
PEEM3, is under
development with an aim of achieving a
resolution of 5 nm
and more than an order of magnitude increase
in transmission
at the nominal resolution of PEEM2. The
resolution and ux
improvement is realized by providing
geometric and chromatic
aberration compensations in the system using
an electron
mirror and a beam separator magnet. The nearly
aberration-free design of the beam separator
is critical to
the performance of third generation PEEMs. In
this paper, we
present the optics design model, optimal
operation
parameters, analyses of aberration impact, as
well as the
mechanical alignment tolerance for PEEM3
separator
prototypes. In particular, we emphasize the
importance of a
new semi-analytical approach to design
complex charged
particle optics using the truncated power
series algebra.
Because of its ability to compute high-order
aberrations,
this approach allows systematic and
comprehensive analyses
of any charged particle optics systems with
analytical
electric and magnetic fields.
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