APS March Meeting 2010
Volume 55, Number 2
Monday–Friday, March 15–19, 2010;
Portland, Oregon
Session T5: Measuring Magnetism at the Nanoscale
2:30 PM–5:30 PM,
Wednesday, March 17, 2010
Room: Portland Ballroom 256
Sponsoring
Unit:
FIAP
Chair: Ernesto Marinero, Hitachi Research Center-San Jose
Abstract ID: BAPS.2010.MAR.T5.2
Abstract: T5.00002 : Soft X-Ray Microscopy: Imaging Magnetism at Small Sizes*
3:06 PM–3:42 PM
Preview Abstract
Abstract
Author:
Peter Fischer
(CXRO/LBNL)
The manipulation of spins on the nanoscale is of both fundamental
and
technological interest. In spin based electronics the observation
that spin
currents can exert a torque onto local spin configurations which
can e.g.
push a domain wall has stimulated significant research activities
in order
to provide a fundamental understanding of the physical processes
involved.
Magnetic soft X-ray microscopy is a unique analytical technique
combining
X-ray magnetic circular dichroism (X-MCD) as element specific
magnetic
contrast mechanism with high spatial and temporal resolution.
Fresnel zone
plates used as X-ray optical elements provide a spatial
resolution down to
currently $<$12nm [1] thus approaching fundamental magnetic
length scales
such as the grain size [2] and magnetic exchange lengths. Images
can be
recorded in external magnetic fields giving access to study
magnetization
reversal phenomena on the nanoscale and its stochastic character
[3] with
elemental sensitivity [4]. Utilizing the inherent time structure
of current
synchrotron sources fast magnetization dynamics with 70ps time
resolution,
limited by the lengths of the electron bunches, can be performed
with a
stroboscopic pump-probe scheme.
In this talk I will review recent achievements with magnetic soft
X-ray
microscopy with focus on current induced wall [5] and vortex
dynamics in
ferromagnetic elements [6].
Future magnetic microscopies are faced with the challenge to
provide both
spatial resolution in the nanometer regime, a time resolution on
a ps to fs
scale and elemental specificity to be able to study novel
multicomponent and
multifunctional magnetic nanostructures and their ultrafast spin
dynamics.\\[4pt]
References\\[0pt]
[1] W. Chao, et al., Optics Express 17(20) 17669 (2009)
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[2] M.-Y. Im, et al, Advanced Materials 20 1750 (2008)
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[3] M.-Y. Im, et al., Phys Rev Lett 102 147204 (2009)
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[4] M.-Y. Im, et al., Appl Phys Lett 95 182504 (2009)
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[5] L. Bocklage, et al., Phys Rev B 78 180405(R) (2008)
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[6] S. Kasai, et al., Phys Rev Lett 101, 237203 (2008)
*This work is supported by the Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, of the U.S. Department of Energy.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2010.MAR.T5.2