• Title/Summary/Keyword: Spin exchange

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Entanglement Generation by Using the Moving Spin (움직이는 스핀입자를 이용한 양자얽힘 생성 방법)

  • Lee, Hyuk-Jae
    • Journal of the Korean Magnetics Society
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    • v.17 no.1
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    • pp.6-9
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    • 2007
  • The generation of entanglement is a very important subject in the quantum computer. Here we suggest the method that generates entanglement between two spin-1/2 particles by using the third moving spin-1/2 particle. We use the $F\"{o}rster$ interaction and the exchange interaction to make the entangled state.

SPIN GLASS BEHAVIOR AND ANTIFERROMAGNETIC EXCHANGE COUPLING IN LASER-DEPOSITED $Zn_{1-x}Co_xO$ THIN FILMS

  • Kim, Hyojin;Kim, Dojin;Ihm, Young-Eon;Kim, Jae-Hyun;Choo, Woong-Kil
    • Proceedings of the Korean Magnestics Society Conference
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    • 2002.12a
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    • pp.94-95
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    • 2002
  • Recently, we have seen a rapid advance in the evolving field of spin electronics (or spintronics). In spintronics, some feasibilities of new electronic applications utilizing spin degree of freedom have been explored. Diluted magnetic semiconductors (DMSs) are premising materials for spintronics because they have both charge and spin degree of freedom in a single substance. DMSs are refereed to semiconductor alloys in which some atoms are randomly substituted for by magnetic atoms. (omitted)

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Fluorine-Induced Local Magnetic Moment in Graphene: A hybrid DFT study

  • Kim, Hyeon-Jung;Jo, Jun-Hyeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.127.1-127.1
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    • 2013
  • Recent experimental evidence that fluorinated graphene creates local magnetic moments around F adatoms has not been supported by semilocal density-functional theory (DFT) calculations where the adsorption of an F adatom induces no magnetic moment in graphene. Here, we show that such an incorrect prediction of the nonmagnetic ground state is due to the self-interaction error inherent in semilocal exchange-correlation functionals. The present hybrid DFT calculation for an F adatom on graphene predicts not only a spin-polarized ground state with a spin moment of ${\sim}1{\mu}_B$, but also a long-range spin polarization caused by the bipartite nature of the graphene lattice as well as the induced spin polarization of the graphene states. The results provide support for the experimental observations of local magnetic moments in fluorinated graphene.

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Magneto resistance in NiO/NiFe/Cu/NiFe spin-valve Sandwiches (NiO/NiFe/Cu/NiFe 스핀-밸브 샌드위치의 자기저항 특성)

  • 김재욱
    • Electrical & Electronic Materials
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    • v.10 no.10
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    • pp.1016-1021
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    • 1997
  • Magneto resistance properties in spin-valve sandwiches with various thickness of nanmagnetic layer in contact with the ferromagnetic NiFe film were investigated. The NiFe layer in contact with the NiO film was pinned by strongly exchange-biased coupling and the free NiFe layer at the film surface induced a sharp change in the magnetoresistance at -5~15Oe due to small coercivity. The NiO/NiFe/Cu/NiFe film showed a magnetoresistance ratio in the range of 2.3~2.9% and a field sensitivity above 2.2%/Oe with various of nonmagnetic layer. The NiO/NiFe/Cu/NiFe film of the field sensitivity above 2.2%/Oe suggests stang possibility of magnetic sensor matter.

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The Magnetization Behavior of Amorphous Fe84-zNb7B8+xCu1 (x0, 1, 4) Alloys

  • Kim, Kyeong-Sup;Moon, Young-Mo;Lee, Jae-Bong;Yu, Seong-Cho;Lim, Woo-Young
    • Journal of Magnetics
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    • v.4 no.1
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    • pp.10-12
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    • 1999
  • We report the salient features of the magnetic properties of amorphous$ Fe_{84-x}Nb_7B_{8+x}Cu_1$ (x=0, 1, 4) alloys. The study of dc-magnetization properties and the ac-susceptibility was carried out. The temperature dependence of the magnetization follows the predictions of spin wave excitations with long wavelengths. Especially, the addition of boron modifies the magnetic properties: the spin wave stiffness increases from 56.8 to 65.7 meV$\AA$2 and Curie temperature increases from 298 K to 352 K. This result indicates a magnetic hardening of the exchange interaction by higher exchange energy. Thus, the substitution of iron by boron favours the increase of magnetic order in this system.

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The Structure, and the Magnetic and Magnetoresistive Characteristics of the Spin Valve Multilayers

  • Stobiecki, T.;Czapkiewicz, M.;Wrona, J.;Powroynik, W.;Stobiecki, F.
    • Journal of Magnetics
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    • v.3 no.3
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    • pp.92-95
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    • 1998
  • In this paper we report the low and high angle diffraction results, and the magnetic and magnetroesistive characteristics of the spin valve multilayer structure prepared by the sputter machine Emerald II in the Balzers Laboratory. The investigated system consists of a ferromagnetic free layer (7 nm NiFe) and a ferromagnetic pinned layer (7 nm NiFe), separated from each other by a nonmagnetic (2.1 nm Cu) spacer. The NiFe pinned layer is fixed by the exchange coupling with an antiferromagnetic layer (10 nm FeMn). For such system the magnetoresistance ratio ΔR/R=3.58%, the interlayer exchange coupling $H_c=6.4$ Oe and the field sensitivity 1.15%/Oe were otained.

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