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相关论文: Absence of Ferromagnetism in Mn-doped Tetragonal Z…

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Neutron and x-ray diffraction studies of Ba(Fe{1-x}Mn{x})2As2 for low doping concentrations (x <= 0.176) reveal that at a critical concentration, 0.102 < x < 0.118, the tetragonal-to-orthorhombic transition abruptly disappears whereas…

Room-temperature ferromagnetism is observed in (110) oriented ZnO films containing 5 at % of Sc, Ti, V, Fe, Co or Ni, but not Cr, Mn or Cu ions. There are large moments, 1.9 and 0.5 muB/atom for Co- and Ti-substituted oxides, respectively.…

材料科学 · 物理学 2009-11-10 M. Venkatesan , C. B. Fitzgerald , J. G. Lunney , J. M. D. Coey

We present a comprehensive study of the energetics and magnetic properties of ZnO clusters doped with 3d transition metals (TM) using ab initio density functional calculations in the framework of generalized gradient approximation + Hubbard…

材料科学 · 物理学 2015-05-20 Nirmal Ganguli , Indra Dasgupta , Biplab Sanyal

The existence of high-temperature ferromagnetism in thin films and nanoparticles of oxides containing small quantities of magnetic dopants remains controversial. Some regard these materials as dilute magnetic semiconductors, while others…

材料科学 · 物理学 2015-05-18 J. M. D. Coey , P. Stamenov , R. D. Gunning , M. Venkatesan , K. Paul

We present a thorough $^{77}$Se NMR study of a single crystal of the magnetoelectric compound Cu$_2$OSeO$_3$. The temperature dependence of the local electronic moments extracted from the NMR data is fully consistent with a magnetic phase…

强关联电子 · 物理学 2010-09-17 M. Belesi , I. Rousochatzakis , H. C. Wu , H. Berger , I. V. Shvets , F. Mila , J. P. Ansermet

Half-metallic ferromagnetism (FM) in single-crystal Ba{0.39(1)}Rb{0.61(1)}Mn2As2 below its Curie temperature TC = 103(2) K is reported. The magnetization M versus applied magnetic field H isotherm data at 1.8 K show complete polarization of…

强关联电子 · 物理学 2015-12-08 Abhishek Pandey , D. C. Johnston

The percentage of substitutional doping of magnetic atoms (Mn) in group-IV-based dilute magnetic semiconductors (DMS) can be increased by co-doping with another conventional electronic dopant (e-dopant) [Zhu et al., Phys. Rev. Lett. 100,…

材料科学 · 物理学 2009-06-04 Hua Chen , Wenguang Zhu , Efthimios Kaxiras , Zhenyu Zhang

Ab initio studies have theoretically predicted room temperature ferromagnetism in crystalline SnO2, ZrO2 and TiO2 doped with non magnetic element from the 1A column as K and Na. Our purpose is to address experimentally the possibility of…

材料科学 · 物理学 2011-01-25 S. K. Srivastava , P. Lejay , B. Barbara , S. Pailhès , V. Madigou , G. Bouzerar

We employ electron paramagnetic resonance (EPR) of the spin probe Mn2+ to study the paraelectric ferroelectric transition in DMAMnF and Mn2 doped DMZnF, which are considered to be model metal organic frameworks (MOF) with a Pb free…

材料科学 · 物理学 2022-02-25 Nandita Abhyankar , Sylvain Bertaina , Maylis Orio , Naresh Dalal

Achieving high temperature ferromagnetism by doping transition metals thin films is seen as a viable approach to integrate spin-based elements in innovative spintronic devices. In this work we investigated the effect of Fe doping on…

材料科学 · 物理学 2015-06-05 Alessio Lamperti , Elena Cianci , Roberta Ciprian , Davide Sangalli , Alberto Debernardi

Otherwise antiferromagnetic chromium is shown to couple ferromagnetically when doped into GaN irrespective of whether the host is a crystal or a cluster. The results on the doped clusters and crystals are obtained from density functional…

材料科学 · 物理学 2007-05-23 G. P. Das , B. K. Rao , P. Jena

We study the electronic states of the magnetically ordered Mn3Pt alloy within the density functional theory. Mn3Pt has been believed that one third of Mn atoms have no magnetic moment in an antiferromagnetic phase (so-called the F-phase)…

材料科学 · 物理学 2009-11-13 Yohei Kota , Hiroki Tsuchiura , Akimasa Sakuma

We study the possibility of d0 ferromagnetism in the compound MgO doped with nitrogen (N). The Haldane-Anderson impurity model is formulated within the tight-binding approximation for determining the host band-structure and the…

材料科学 · 物理学 2009-11-13 Bo Gu , Nejat Bulut , Timothy Ziman , Sadamichi Maekawa

The doping effect of Sr and transition metals Mn, Fe, Co into the direct-gap semiconductor LaZnAsO has been investigated. Our results indicate that the single phase ZrCuSiAs-type tetragonal crystal structure is preserved in…

The structural and magnetic properties of polycrystalline YMn1-xMxO3 (M = Ti, Fe, Ga; x = 0, 0.1) have been studied by neutron powder diffraction and magnetic measurements to probe the effect of Mn site doping on the frustration behavior…

材料科学 · 物理学 2013-08-13 Neetika , A. Das , C. L. Prajapat , S. S. Meena

The spin states at the surface of epitaxial thin films of hematite, both undoped and doped with 1% Ti, Sn or Zn, respectively, were probed with x-ray magnetic linear dichroism (XMLD) spectroscopy. Morin transitions were observed for the…

The structural and magnetic behavior of Mn-site doped intermetallic manganese silicide alloys of nominal compositions Mn$_{5-x}$A$_x$Si$_3$ ($x$ = 0.05, 0.1, 0.2 and A = Ni, Cr) have been investigated with a focus to the inverted hysteresis…

材料科学 · 物理学 2020-06-01 S. C. Das , K. Mandal , N. Khamaru , S. Pramanick , S. Chatterjee

Neutron scattering has been used to study the magnetic order and spin dynamics of the colossal magnetoresistive pyrochlore Tl_2Mn_2O_7. On cooling from the paramagnetic state, magnetic correlations develop and appear to diverge at T_C (123…

强关联电子 · 物理学 2009-10-31 J. W. Lynn , L. Vasiliu-Doloc , M. A. Subramanian

The magnetism in 12.5% and 25% Mn delta-doped cubic GaN has been investigated using the density-functional theory calculations. The results show that the single-layer delta-doping and half-delta-doping structures show robust ground state…

材料科学 · 物理学 2009-01-20 Xingtao Jia , Wei Yang , Minghui Qin , Xinglai Zhang , Xindong Cui , Mingai Sun

We have studied the influence of intrinsic and extrinsic defects in the magnetic and electrical transport properties of Co-doped ZnO thin films. X ray absorption measurements show that Co substitute Zn in the ZnO structure and it is in the…