中文
相关论文

相关论文: Mn and Fe Impurities in MgB_{2}

200 篇论文

A formalism is developed to treat magnetic impurities in a Mott-Hubbard antiferromagnetic insulator within a representation involving multiple orbitals per site. Impurity scattering of magnons is found to be strong when the number of…

强关联电子 · 物理学 2009-10-31 Avinash Singh , Prasenjit Sen

In order to find out if magnetic impurities can mediate interactions between quasiparticles in metals, we have measured the effect of a magnetic field B on the energy distribution function f(E) of quasiparticles in two silver wires driven…

介观与纳米尺度物理 · 物理学 2009-11-10 A. Anthore , F. Pierre , H. Pothier , D. Esteve

Effects of magnetic impurity on the superconductivity has been investigated in Mg1-xMnB2. With increase of Mn concentration x, the lattice constant c (perpendicular to the boron sheet) decreases at a rate of -1.4 % (= dlnc/dx), while a…

超导电性 · 物理学 2009-11-07 Sheng Xu , Yutaka Moritomo , Kenichi Kato , Arao Nakamura

Metals with many bands at the Fermi level can have different band dependent gaps in the superconducting state. The absence of translational symmetry at an interface can induce interband scattering and modify the superconducting properties.…

凝聚态物理 · 物理学 2009-11-07 E. Bascones , F. Guinea

We study effects of nonmagnetic impurities in a Spin Bose-Metal (SBM) phase discovered in a two-leg triangular strip spin-1/2 model with ring exchanges (D. N. Shenget al, arXiv:0902.4210). This phase is a quasi-1D descendant of a 2D spin…

强关联电子 · 物理学 2010-09-21 Hsin-Hua Lai , Olexei I. Motrunich

We present a computational study of individual and pairs of substitutional Mn impurities on the (110) surface of GaAs samples based on density functional theory. We focus on the anisotropy properties of these magnetic centers and their…

强关联电子 · 物理学 2011-08-29 M. Fhokrul Islam C. M. Canali

We present the first results of directional point-contact measurements in Mg_{1-x}Mn_{x}B_2 single crystals, with x up to 0.015 and bulk T_c down to 13.3 K. The order parameters Delta_{sigma} and Delta_{pi} were obtained by fitting the…

In this paper we summarize the effects of magnetic and nonmagnetic impurities on the spin dynamics in Febased superconductors and their parent compounds. The effects of chemical substitution, vacancies, and disorder on the suppression or…

We study nonmagnetic impurity effects in MgB$_{2}$ using the quasiclassical equations of superconductivity for a weak-coupling two-band model. Parameters in the model are fixed so as to reproduce experiments on MgB$_{2}$ as closely as…

超导电性 · 物理学 2009-11-10 Koichi Watanabe , Takafumi Kita

Using first-principles calculations, we investigated the impact of chromium (Cr) and vanadium (V) impurities on the magnetic anisotropy and spin polarization in Fe/MgO magnetic tunnel junctions. It is demonstrated using layer resolved…

材料科学 · 物理学 2016-01-25 A. Hallal , B. Dieny , M. Chshiev

Applying the generalization of the model for chain formation in break-junctions [JPCM 24, 135501 (2012)], we study the effect of light impurities on the energetics and elongation properties of Pt and Ir chains. Our model enables us with a…

介观与纳米尺度物理 · 物理学 2014-10-02 Solange Di Napoli , Alexander Thiess , Stefan Blügel , Yuriy Mokrousov

We investigate a magnetic impurity in Bernal stacked bilayer graphene by a non-perturbative numerical exact approach. In the two cases we study, impurity is placed on the top of two different sublattices (A and B) in bilayer graphene. We…

强关联电子 · 物理学 2012-06-05 J. H. Sun , F. M. Hu , H. K. Tang , H. Q. Lin

The effect of a magnetic (S=1/2) impurity coupled to a 2D system of correlated electrons (described by the t--J model) is studied by exact diagonalisations. It is found that, if the exchange coupling of the impurity with the neighboring…

凝聚态物理 · 物理学 2016-08-31 D. Poilblanc , D. J. Scalapino , W. Hanke

The effects of dilute Zn impurities on the uniform magnetic susceptibility are calculated in the normal metallic state for a model of the spin fluctuations of the layered cuprates. It is shown that scatterings from extended impurity…

强关联电子 · 物理学 2009-10-31 N. Bulut

A new route to $d^0$ magnetism is established with help of the first principles methods. Non-magnetic interstitial impurities from group 14 in the periodic table are found to induce $p$-orbital magnetism in polycrystalline PbO-type…

材料科学 · 物理学 2015-06-15 J. Berashevich , A. Reznik

Measurements have been performed of the resistivity of the samples of MgB2, AlB2 and AgB2. The samples show presence of impurities. Analyzing the data in terms of the impurity scattering, electron-phonon scattering, and weak localization it…

超导电性 · 物理学 2009-11-11 R. Lal , V. P. S. Awana , K. P. Singh , H. Kishan , A. V. Narlikar

The substitution of Mn in the III-V diluted magnetic semiconductors leads to a strong electron scattering on impurities. Besides the features induced in the valence band by the hybridization with the Mn d-states, also the conduction band is…

材料科学 · 物理学 2007-05-23 J. Masek , F. Maca

We have performed ab initio calculations to systematically investigate electronic properties and magnetism of insulating non-magnetic beryllium monoxide nanotubes induced by non-magnetic sp impurities: boron, carbon and nitrogen. We found…

Magnetoresistance measurements on the magnetic semiconductor (In,Mn)Sb suggest that magnetic scattering in this material is dominated by isolated Mn$^{2+}$ ions located outside the ferromagnetically-ordered regions when the system is below…

其他凝聚态物理 · 物理学 2009-11-11 M. Csontos , T. Wojtowicz , X. Liu , M. Dobrowolska B. Jankó , J. K. Furdyna , G. Mihály

We theoretically consider the effects of having unintentional charged impurities in laterally coupled two-dimensional double (GaAs) quantum dot systems, where each dot contains one or two electrons and a single charged impurity in the…

介观与纳米尺度物理 · 物理学 2015-05-27 Nga T. T. Nguyen , S. Das Sarma