• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.100-101
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• 2002

자성가넷 박막은 가시광선 영역에서 큰 값의 페러데이 회전각을 갖고, 광흡수가 적어 우수한 자기광학 특성을 나타내는 재료로 널리 알려져 있다.[1]. 또한 가넷에 Bi를 치환하면 성능지수가 크게 증가하는 것이 알려져 있으므로 현재 연구개발의 초점이 Bi치환 가넷 박막에 모아지고 있다. 가넷박막을 제조하는 방법에 있어 종래에는 스퍼터링법, LPE법, 열분해법 등으로 연구되어 왔으나, 스퍼터링법과 LPE법의 경우 공정이 복잡하고 고가의 장치가 필요한 단점이 있으며, 열분해법의 경우에는 잔존하는 일부 분해가스로 인하여 박막이 다공질화 될 우려가 있다.[2]. (중략)

• Electrical & Electronic Materials
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• v.1 no.3
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• pp.228-234
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• 1988

본 논문에서는 자기 버블 및 VBL 기억 소자의 기본적인 동작원리 및 사용되는 재료 특히 자기 가넷 박막의 설계와 제조과정을 살펴보았다. 자기 가넷의 가장 큰 장점중의 하나는 응용 분야에 따라 원하는 자기적 특성을 갖는 박막을 쉽게 성장시킬 수 있다는 장점이다. 그러나 현재의 결과로는 0.3.mu.m 이하의 직경을 갖는 버블 박막은 가넷을 이용하여서는 제조하기 힘들므로 그보다 작은 버블을 원하면 육방정계 페라이트나 비정질 합금을 이용하여야 할 것으로 보인다. VBL소자의 경우 0.5.mu.m직경의 버블로 1Gbit/$cm^{2}$의 기록 밀도가 예상되므로 가까운 장래에는 가넷이외의 재료를 생각할 필요는 없을 것이다. 현재의 연구 추세로는 0.3.mu.m직경의 버블을 이용한 버블 소자가 개발되면 또는 그 이전에라도 VBL 소자가 버블 소자를 대치할 것으로 보여 한동안 가넷이외의 재료에 대한 연구는 활발하지 않을 것으로 전망된다.

• Journal of the Korean Magnetics Society
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• v.17 no.6
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• pp.246-252
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• 2007

This paper describes the effect of the mixing ratio of starting materials and the growth parameters of magnetic garnet films by LPE on the properties of the films and suggests the conditions to obtain the films suitable for the Faraday rotators of the optical CTs. The properties of the films investigated for the evaluation of the films were thickness, surface morphology, X-ray diffraction, lattice constant, lattice mismatch between film and substrate (single crystal nonmagnetic wafer), and Faraday rotation angle. Optical CTs have been fabricated and evaluated using the films grown.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.5
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• pp.182-187
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• 2005

The FT-IR absorption spectrum by the lattice vibrations of ruby and garnet obtained from FT-IR shows quite different characteristics. By the UV-VIS spectroscopy it was found that the ruby has two transmission bands in red and blue region, while garnet has only one transmission band in red region. The color filter to distinguish ruby from garnet was developed and named HWANG JI HO filter. Through the HWANG JI HO filter, ruby was shown in blue color and garnet was shown in dark red color because of the only the blue region transmittance of the filter. Other red stones, such as spinel, tourmaline were shown in dark red color like as garnet. The ruby could be recognized easily from the red stone.

• Journal of the Korean Magnetics Society
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• v.3 no.2
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• pp.143-148
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• 1993

$Bi_{x}Dy_{3-x}Al_{1}Fe_{4}O_{12}$(x=1, 1.2, 1.5) magnetic garnet films were fabricated on the glass substrates by pyrolysis method. As the Bi content was increased, the saturation magnetization increased from 5 emu/cc to 11 emu/cc and all the films showed perpendicular magnetic anisotropy. As the content of Bi was increased, Faraday rotation angle (${\theta}_F$) at 780 nm of the films increased from $0.11^{\circ}/\mu\textrm{m}$ to $0.20^{\circ}/\mu\textrm{m}$ and the garnet crystallization temperature decreased from $660^{\circ}C$ to $630^{\circ}C$. Also, the coercivity ($H_{c}$) decreased from 1200 Oe to 600 Oe and the grain sizes increased. $H_{c}$ decreased from 1750 Oe to 1200 Oe and ${\theta}_F$ increased due to the interference of the reflected laser light as the thickness of the films increased from $2000\;{\AA}$ to $4000\;{\AA}$.

• Journal of the Korean Magnetics Society
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• v.4 no.3
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• pp.214-218
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• 1994

$Y_{3}Fe_{5}O_{12}$ based garnet films(thin or thick) offer a great promise for the application of microwave communication components. We investigated the magnetic and crystallographic preperties of $Y_{3}Fe_{5}O_{12}$ thick films prepared by KrF eximer laser ablation of a stoichiometric garnet target. It was possible to obtain almost epitaxially oriented films on $Al_{2}O_{3}$(1102) plane. Although the crystalline quality depends on substrate temperature and $O_{2}$ partial pressure used($Po_{2}$), 4.1m thick films of $4{\pi}M_{s}=1300$ Gauss and $H_{c}=37.5$ Oe were obtained at the substrate temperature of $700^{\circ}C$ with the $Po_{2}$ of 100 mTorr after annealing the as-deposited films at $700^{\circ}C$ for 2 hours. These films are expected to be used for magnetostatic spin wave filters at narrow bandwidth frequency.

• Proceedings of the Korean Magnestics Society Conference
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• 2012.05a
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• pp.26-27
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• 2012

• YAKHAK HOEJI
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• v.37 no.3
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• pp.209-215
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• 1993

Basic drugs could be extracted as ion-paired complexes with Lumogallion, Superchrome Garnet Y and their alkyl derivatives from aqueous acid solution, and then determined fluoro-metrically after addition of aluminum ion. The analysis was carried out as follows; To a 1 ml portion of basic drugs (10$^{-9}$~2$\times$0$^{-8}$mole/ml), 1ml of 0.01w/v% fluorescent reagent solution, and 10ml of dichloroethane are added. The mixture is stirred for 1 minute. After standing for a few minutes, the dichloroethane layer is transfered to 1 ml of 0.1w/v% Al(NO$_{3}$)$_{3}$ ethanol solution. After mixing, and standing for 30 minutes at room temperature, the fluorescence intensity is measured with each maximum excitation and emission wavelength. The reagent blank is run through the whole procedure. From the degree of enhancement of fluorescence intensity, hexyl and dodecyl lumogallion and Superchrome Garnet Y were judged to be the useful one of fluorescent reagent for basic drugs analysis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1988.10a
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• pp.47-49
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• 1988

This paper discusses dynamic properties of bubble garnet thin films. The dynamic properties considered are Gilbert damping parameters, saturation velocity, and wall mobility. The parameters are evaluated to facilitate the search for desirable garnet thin film compositions. Given bubble diameter and Q-value, the computer prints out all compositions which meet the desired requirements. The computer model determines magnetization, anisotropy, damping, velocity, mobility among others from the film compositions. The computer modeling program is described by an algorithm detailing its operation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.12
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• pp.1132-1137
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• 2011

MRE(magneto-rheological elastomers) is a material which shows reversible and various modulus in magnetic field. Comparing to conventional rubber vibration isolator, MREs are able to absorb vibration of broader frequency range. These characteristic phenomena result from the orientation of magnetic particles named carbonyl iron powder(CIP) in rubber matrix. In this paper, simulation on variation rate of shear modulus for anisotropic MRE due to volume fraction of CIP and an effective permeability model was applied to predict the field-induced shear modulus of MREs. Also, the variation rate of shear modulus for anisotropic MRE was derived using magneto-mechanical theory. Based on Maxwell-Garnett mixing rule, the increment of shear modulus was calculated to evaluate the shear modulus of MREs with column structure of CIP due to induced current. The simulation results on variation rate of shear modulus can be applied to the variable mechanical system of MRE such as tunable vibration absorber, stiffness variable bush and mount.