• 제목/요약/키워드: ferromagnet

검색결과 77건 처리시간 0.034초

비정질 MnGe를 이용한 Magnetic Semiconductor 특성에 대한 연구

  • 이긍원;정치운;임상호;송상훈
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2002년도 동계연구발표회 논문개요집
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    • pp.76-77
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    • 2002
  • 최근 거대자기저항(Giant magneto resistance)과 성질상으로 닮고 spin-valve와 같은 작용을 하는 ferromagnet(FM)/semiconductor, magnetic semiconductor(MS)/semiconductor 등의 다층막이 만들어지고 있으며, 비자성반도체에 spin-injection을 통한 spin-dependent electronic devices의 제작을 위한 연구가 활발히 진행중이다. 이처럼 III-FM-V, II-FM-Ⅵ, IV-FM 구조의 자성반도체(Magnetic semiconductor)에 대한 연구는 자기적 요소에 기반을 둔 반도체로의 적용가능성을 보임으로 많은 주목을 끌고 있다. 우리가 선택한 MnGe이 다른 자성반도체에 대해 상대적으로 가지는 이점은 다음과 같다. (중략)

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Magneto-transport properties of CVD grown MoS2 lateral spin valves

  • 전병선;이상선;황찬용
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.336-336
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    • 2016
  • We have investigated magneto-transport properties in a MoS2 lateral spin-valve structures for different ferromagnetic CoFe electrode shapes and MoS2 channel lengths. For these devices, high quality and large-scale MoS2 thin films were synthesized through sulfurization of epitaxial MoO3 films and these sulfurized-MoO3 thin films properties are in good agreements with measurements on exfoliated MoS2 film. Magneto-transport measurements show a clear rectangular magnetoresistance signal of 0.16% and a spin polarization of 0.00012%. By using the one-dimensional spin diffusion equation, we extracted the spin diffusion length and coefficient, finding them to be 12 nm and $1.44{\times}10-3cm2/s$, respectively. These small values of magnetoresistance and spin polarization could be enhanced by appeasement of conductivity mismatch between the ferromagnet and semiconductor interface.

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마그네트 기반 감속기의 민감도 해석 (Sensitivity Analysis of the Speed Reducer using Magnetic Force)

  • 정광석
    • 융복합기술연구소 논문집
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    • 제4권2호
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    • pp.11-15
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    • 2014
  • Magnet gear transfers a high speed torque of the driving side to a low speed following side. Of course, the torque is amplified as much as a ratio between pole number of magnet gears constituting both sides through ferromagnet modulator. However, the parameters of the overall magnetic system influence the transmitting torque strongly. They include a pole number of permanent magnet, magnet thickness, reducing ratio, harmonic modulator thickness, and open ratio etc. In this paper, the influences of the parameters are analyzed using finite element method tool. By comparison, a desirable design specification is proposed, including a recommended modulator pattern.

Superconducting Properties of $BaFe_{1.8}Co_{0.2}As_2$

  • Lee, Sung-Ik;Kim, Soo-Hyun;Choi, Chang-Ho;Jung, Myung-Hwa;Choi, Ki-Young;Wang, X.F.;Chen, X.H.;Noh, Jae-Dong;Wang, X.L.
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 2009년도 Korea Superconductivity Society Meeting 2009
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    • pp.18-18
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    • 2009
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Electrical Spin Transport in n-Doped In0.53Ga0.47As Channels

  • Park, Youn-Ho;Koo, Hyun-Cheol;Kim, Kyung-Ho;Kim, Hyung-Jun;Han, Suk-Hee
    • Journal of Magnetics
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    • 제14권1호
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    • pp.23-26
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    • 2009
  • Spin injection from a ferromagnet into an n-doped $In_{0.53}Ga_{0.47}As$ channel was electrically detected by a ferromagnetic detector. At T = 20 K, using non-local and local spin-valve measurements, a non-local signal of $2\;{\mu}V$ and a local spin valve signal of 0.041% were observed when the bias current was 1 mA. The band calculation and Shubnikov-de Haas oscillation measurement in a bulk channel showed that the gate controlled spin-orbit interaction was not large enough to control the spin precession but it could be a worthy candidate for a logic device using spin accumulation and diffusion.

PRESSURE DEPENDENCE OF THE CURIE TEMPERATURE IN MnAlGe

  • Endo, S.;Matsuzaki, H.;Ono, F.;Kanomata, T.;Kaneko, T.
    • 한국자기학회지
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    • 제5권5호
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    • pp.380-382
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    • 1995
  • The pressure dependence of the Curie temperature was determined in 2-dimensional like ferromagnet, MnAlGe up to a maximum pressure of 7.5 Gpa through measurements of electric resistance vs temperature curves. The pressure coefficient was positive with a considerably high rate of 9 K/GPa in the low pressure ragion, while it decreased gradually down to one order of magnitude smaller value at the maximum pressure. It was concluded that ther is an upper limit of about 550 K in the super-exchange type ferromagnetic interaction between Mn layers.

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