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Title: Observation of injection and pinning of domain walls in magneticnanowires using photoemission electron microscopy

Abstract

Photoemission electron microscopy is used to explore the injection and pinning of magnetic domain walls in 250-nm-wide, 20-nm-thick Permalloy nanowires. Domain walls are injected from a micron-sized elliptical nucleation pad at one end of the nanowire. A vortex-like structure is readily nucleated in this pad at low magnetic fields 15 Oe, whereas injection of a domain wall into the nanowire requires significantly larger fields 60 Oe. Domain walls are pinned in the nanowire at notches patterned along the wires edges. The domain walls are observed to have vortex-like structures with chiralities that vary in successive experiments.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE Director. Office of Science. Office of AdvancedScientific Computing Research. Office of Basic Energy Sciences; Department of Defense. Defense Advanced Research ProjectsAgency
OSTI Identifier:
892949
Report Number(s):
LBNL-60778
Journal ID: ISSN 0003-6951; APPLAB; R&D Project: A58128; BnR: KC0204016; TRN: US200623%%646
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 87; Related Information: Journal Publication Date: 2005
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ELECTRON MICROSCOPY; MAGNETIC FIELDS; NUCLEATION; PERMALLOY; PHOTOEMISSION; advanced light source als

Citation Formats

Thomas, Luc, Rettner, Charles, Hayashi, Masamitsu, Samant, MaheshG., Parkin Stuart S.P., Doran, Andrew, and Scholl, Andreas. Observation of injection and pinning of domain walls in magneticnanowires using photoemission electron microscopy. United States: N. p., 2005. Web. doi:10.1063/1.2139842.
Thomas, Luc, Rettner, Charles, Hayashi, Masamitsu, Samant, MaheshG., Parkin Stuart S.P., Doran, Andrew, & Scholl, Andreas. Observation of injection and pinning of domain walls in magneticnanowires using photoemission electron microscopy. United States. doi:10.1063/1.2139842.
Thomas, Luc, Rettner, Charles, Hayashi, Masamitsu, Samant, MaheshG., Parkin Stuart S.P., Doran, Andrew, and Scholl, Andreas. Mon . "Observation of injection and pinning of domain walls in magneticnanowires using photoemission electron microscopy". United States. doi:10.1063/1.2139842.
@article{osti_892949,
title = {Observation of injection and pinning of domain walls in magneticnanowires using photoemission electron microscopy},
author = {Thomas, Luc and Rettner, Charles and Hayashi, Masamitsu and Samant, MaheshG. and Parkin Stuart S.P. and Doran, Andrew and Scholl, Andreas},
abstractNote = {Photoemission electron microscopy is used to explore the injection and pinning of magnetic domain walls in 250-nm-wide, 20-nm-thick Permalloy nanowires. Domain walls are injected from a micron-sized elliptical nucleation pad at one end of the nanowire. A vortex-like structure is readily nucleated in this pad at low magnetic fields 15 Oe, whereas injection of a domain wall into the nanowire requires significantly larger fields 60 Oe. Domain walls are pinned in the nanowire at notches patterned along the wires edges. The domain walls are observed to have vortex-like structures with chiralities that vary in successive experiments.},
doi = {10.1063/1.2139842},
journal = {Applied Physics Letters},
number = ,
volume = 87,
place = {United States},
year = {Mon Dec 19 00:00:00 EST 2005},
month = {Mon Dec 19 00:00:00 EST 2005}
}
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