• 제목/요약/키워드: electronic structure and magnetism

검색결과 68건 처리시간 0.023초

A First-principles Study on Magnetism of Al Impurity in bcc Fe

  • Rahman, Gul;Kim, In-Gee
    • Journal of Magnetics
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    • 제16권1호
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    • pp.1-5
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    • 2011
  • The magnetism and electronic structure of bcc $Al_1Fe_{26}$ was investigated by means of first-principles calculations with and without spin-orbit coupling (SOC). From the calculated total energy, the SOC corrected system is shown to be approximately 5 meV per atom lower than the SOC uncorrected system. The induced spin magnetic moment at the Al site was -0.125 ${\mu}_B$ without SOC and -0.124 ${\mu}_B$ with SOC. The orbital magnetic moments were calculated to be 0.002 ${\mu}_B$ in [$\overline{1}$00] direction for Al. The electronic structures showed the nearest neighbor antiferromagnetic interaction between Fe and Al to be essential for determining the magnetism of the $Al_1Fe_{26}$ system.

Electronic Structure and Magnetism of CrP/SrBi Interface: A First Principles Study

  • Bialek, Beata;Lee, Jae-Il
    • Journal of Magnetics
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    • 제12권3호
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    • pp.93-96
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    • 2007
  • We investigated the electronic structure and magnetic properties of zinc-blende CrP/SrBi interface by using the all-electron full-potential linearized augmented plane wave method within the generalized gradient approximation. It is found that the half-metallicity is destroyed when the two half-metals are in contact. Magnetic moments of the atoms forming the supercell differ considerably from the respective values obtained for the bulk structures of the two materials. Cr atoms being and not being in contact with Bi atoms have magnetic moment 3.43 and $2.69{\mu}_B$, respectively. Bi atoms lose their majority electrons which results in their negative polarization. Alkaline Sr atoms are very weakly negatively polarized. The spin distribution within the supercell is such that well separated regions of positive and negative polarization are seen, especially around the layer of P atoms being in contact with the layer of Sr atoms.

Surface and Interface Magnetism in CoTi/FeTi/CoTi(110)

  • Lee G.H.;Jin Y. J.;Lee J. I.;Hong S.C.
    • Journal of Magnetics
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    • 제10권1호
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    • pp.1-4
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    • 2005
  • We investigated the electronic structures and the magnetic properties of Ti-based intermetallic system of CoTi/FeTi/CoTi(110) surface and interface by using the all-electron full potential linearized augmented plane wave (FLAPW) method within the generalized gradient approximation (GGA). The calculated magnetic moments of interface Co and Fe atoms are 0.65 and 0.15 μ/sub B/, respectively. Surface and interface magnetism of CoTi/FeTi/CoTi(110) are discussed using the calculated density of states (DOS) and the spin densities.

(CrAs)3(MnAs)3(110) 초격자의 전자구조와 자성에 대한 제일원리 연구 (First-principles Study on the Magnetism and Electronic Structure of (CrAs)3(MnAs)3(110) Superlattice)

  • 이재일;홍순철
    • 한국자기학회지
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    • 제16권2호
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    • pp.111-114
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    • 2006
  • Zinc-blonde 구조를 가지는 CrAs와 MnAs에서 (110)면 원자층으로 이루어진 초격자의 자성을 제일원리 방법을 이용하여 연구하였다. 이를 위해 CrAs와 MnAs의 (110)층이 각기 세 층씩 교대로 반복되는 $(CrAs)_3(MnAs)_3(110)$ 초격자계의 전자구조를 총 퍼텐셜 선형보강평면파동(FLAPW) 에너지띠 방법을 이용하여 계산하였다. Cr-As로 이루어진 층과 Mn-As로 이루어진 층이 접합되는 계면에 있는 Cr과 Mn원자의 자기모멘트를 계산한 결과 각기 $3.07\;\mu_B$$3.74\;\mu_B$로 가운데 층의 Cr과 Mn의 자기모멘트 값인 $3.06\;\mu_B$$3.76\;\mu_B$보다 약간 크거나 작았다. 계산된 상태밀도로부터 이 계의 전자구조와 반쪽금속성을 고찰하였다.

Correlation between Structures and Magnetism in Iron: Ferromagnetism and Antiferromagnetism

  • Lee, Dong-Kook;Hong, Soon-Cheol
    • Journal of Magnetics
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    • 제12권2호
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    • pp.68-71
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    • 2007
  • Even a pure bulk Fe has a complicated magnetic phase and its magnetism is still needed to be clarified. In this study we investigated the magnetism of bcc and fcc bulk Fe with total energy calculations as functions of atomic volume. The full-potential linearized augmented plane wave method was adopted within a generalized gradient approximation. The ground state of bulk Fe is confirmed to be of ferromagnetic (FM) bcc. For fcc structured Fe an antiferromagnetic (AFM) state is more stable compared to FM states which exist as low spin and high spin states. The stable AFM states were found to accompany a tetragonal distortion, while the FM states remained in a cubic symmetry. At an expanded lattice constant a high spin FM state was calculated to be able to be stabilized with significant enhanced magnetic moment compared to the value of the ground state, bcc FM.

Electronic Structure and Magnetism of Alloying Elements Substituted B2 FeAl Intermetallic Compounds: A Density Functional Study

  • Yun, Won Seok;Lee, Jee Yong;Kim, In Gee
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2012년도 자성 및 자성재료 국제학술대회
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    • pp.130-131
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    • 2012
  • In this study, the thermodynamic and magnetic properties of alloying element substituted B2 FeAl systems have been investigated using the all-electron FLAPW method based on the GGA. It was shown that the important changes take place in the structural properties as well as in the magnetism when alloying element is substituted by Fe or Al site in B2 FeAl. Detailed discussion on the thermodynamic and magnetic properties and electronic structure of these intermetallic compounds will be given.

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