Abstract
The magnetic domain structures of Ni micro ring (the inner and outer diameters are changed in a micrometer region) and micro dot array with different shapes and with a small separation between dots were observed by the combined method of photoelectron emission microscopy and X-ray magnetic circular dichroism. For the micro rings with a large inner diameter, a flux-closure (FC) domain structure tends to appear more easily than for those with a small inner diameter. This means that the FC domain structure of the micro rings with a large inner diameter is energetically more stable than those of the micro rings with a small inner diameter and the disks. After applying an external pulsed magnetic field of about 40 mT in the in-plane direction, each domain structure switched to an almost perfect single-domain structure. Because of the absence of a central vortex core in the ring as compared with the disks, exchange energy decreases substantially. These phenomena are discussed along with the simulation results. For the micro dot array, the interaction between dots was directly observed. Particularly for the circular disks with a small diameter showing FC domains, no interaction is observed due to the lack of stray fields from each disk. On the other hand, dots with multi domain structures interacted. These types of information may provide us fundamental knowledge for designing high-density magnetic recording media.
| Original language | English |
|---|---|
| Pages (from-to) | 4179-4184 |
| Number of pages | 6 |
| Journal | Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers |
| Volume | 43 |
| Issue number | 7 A |
| DOIs | |
| Publication status | Published - Jul 2004 |
| Externally published | Yes |
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Keywords
- Magnetic domain
- MCD
- Mesoscopic structures
- Microscopy
- PEEM
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)
Cite this
Magnetic domain imaging of Ni micro ring and micro dot array by photoelectron emission microscopy. / Okuda, Taichi; Kiwata, Hideyuki; Matsushima, Takeshi; Wakita, Takanori; Harasawa, Ayumi; Ono, Kanta; Kihara, Takayuki; Oshima, Masaharu; Yokoo, Atsushi; Kinoshita, Toyohiko.
In: Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers, Vol. 43, No. 7 A, 07.2004, p. 4179-4184.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Magnetic domain imaging of Ni micro ring and micro dot array by photoelectron emission microscopy
AU - Okuda, Taichi
AU - Kiwata, Hideyuki
AU - Matsushima, Takeshi
AU - Wakita, Takanori
AU - Harasawa, Ayumi
AU - Ono, Kanta
AU - Kihara, Takayuki
AU - Oshima, Masaharu
AU - Yokoo, Atsushi
AU - Kinoshita, Toyohiko
PY - 2004/7
Y1 - 2004/7
N2 - The magnetic domain structures of Ni micro ring (the inner and outer diameters are changed in a micrometer region) and micro dot array with different shapes and with a small separation between dots were observed by the combined method of photoelectron emission microscopy and X-ray magnetic circular dichroism. For the micro rings with a large inner diameter, a flux-closure (FC) domain structure tends to appear more easily than for those with a small inner diameter. This means that the FC domain structure of the micro rings with a large inner diameter is energetically more stable than those of the micro rings with a small inner diameter and the disks. After applying an external pulsed magnetic field of about 40 mT in the in-plane direction, each domain structure switched to an almost perfect single-domain structure. Because of the absence of a central vortex core in the ring as compared with the disks, exchange energy decreases substantially. These phenomena are discussed along with the simulation results. For the micro dot array, the interaction between dots was directly observed. Particularly for the circular disks with a small diameter showing FC domains, no interaction is observed due to the lack of stray fields from each disk. On the other hand, dots with multi domain structures interacted. These types of information may provide us fundamental knowledge for designing high-density magnetic recording media.
AB - The magnetic domain structures of Ni micro ring (the inner and outer diameters are changed in a micrometer region) and micro dot array with different shapes and with a small separation between dots were observed by the combined method of photoelectron emission microscopy and X-ray magnetic circular dichroism. For the micro rings with a large inner diameter, a flux-closure (FC) domain structure tends to appear more easily than for those with a small inner diameter. This means that the FC domain structure of the micro rings with a large inner diameter is energetically more stable than those of the micro rings with a small inner diameter and the disks. After applying an external pulsed magnetic field of about 40 mT in the in-plane direction, each domain structure switched to an almost perfect single-domain structure. Because of the absence of a central vortex core in the ring as compared with the disks, exchange energy decreases substantially. These phenomena are discussed along with the simulation results. For the micro dot array, the interaction between dots was directly observed. Particularly for the circular disks with a small diameter showing FC domains, no interaction is observed due to the lack of stray fields from each disk. On the other hand, dots with multi domain structures interacted. These types of information may provide us fundamental knowledge for designing high-density magnetic recording media.
KW - Magnetic domain
KW - MCD
KW - Mesoscopic structures
KW - Microscopy
KW - PEEM
UR - http://www.scopus.com/inward/record.url?scp=4644249181&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=4644249181&partnerID=8YFLogxK
U2 - 10.1143/JJAP.43.4179
DO - 10.1143/JJAP.43.4179
M3 - Article
AN - SCOPUS:4644249181
VL - 43
SP - 4179
EP - 4184
JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
SN - 0021-4922
IS - 7 A
ER -