Neutron Scattering from Magnetic Materials part 15 pptx

... atoms, ˇ V M = 2π ¯ h 2 m  Np z Np x −iNp y Np x +iNp y −Np z  , (60) where the magnitude of the magnetic scattering length p is associated with a given atomic magnetic moment. The magnetic scattering length p arises from the atom’s unpaired elec- trons ... reflectivity measurements of magnetic films and multilay- ers. Here we will present a derivation of the dynamical theory fo...

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... Tasset, Physica B 156 157 627 (1989). [9] P.J. Brown, J.B. Forsyth and F. Tasset, Proc. Roy. Soc. London Ser. A 442 147 (1993). [10] P.J. Brown, in: Neutron Scattering from Magnetic Materials, ed. ... Bragg reflections from magnetic structures with zero propagation vector can contain both nuclear and magnetic scattering. They give the interference terms in the polarised neutr...

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... different aspects of neutron scattering from magnetic mate- rials. I intentionally chose the title Neutron Scattering from Magnetic Materials rather than Magnetic Neutron Scattering to emphasize ... mainly consider magnetic neutron scattering. However, neutron scattering intensity from magnetic materials is a superposition of both types of scattering. In or...

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... of the magnetic moments. 5.1.1. Spin–slip magnetic structures of holmium. The magnetic structure of Ho has been investigated both by neutron and by more recently developed X-ray magnetic scattering [27–29]. ... structures discussed above. If the magnetic structure is antiferromagnetic with a propagation vector k =0 then magnetic Bragg scattering is present at positions whic...

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... 135 5.1. First example,  k =0 135 5.2. Second example,  k =0 146 References 150 NEUTRON SCATTERING FROM MAGNETIC MATERIALS Edited by Tapan Chatterji © 2006 Elsevier B.V. All rights reserved 93 88 ... directions of the magnetic scatterings with respect to the incident neutron beam, the magnetic periodicity (defined by wave vectors  k in the reciprocal space) can be deduced,...

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... iron. At the opposite end, magnetic scattering in the paramagnetic β and γ phases of solid oxygen [46–48] give examples of antiferromagnetic correlations. Figure 26 represents the magnetic pattern obtained, ... possible to extract the magnetic scattering from differences between measurements (both spin-flip or both non-spin-flip) with polariza- tion vertical and with polarization al...

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... (27) Here the neutron scattering cross-section has been broken into two parts: (1) the part mul- tiplied by (1 −Q 2 z ) is the longitudinal part of the cross-section, while the term multiplied Magnetic ... in bilayer manganite La 2−2x Sr 1+2x Mn 2 O 7 315 6.Concludingremarks 327 Acknowledgments 328 References 328 NEUTRON SCATTERING FROM MAGNETIC MATERIALS Edited by Tapan...

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... spectrometer. The neutron coherent inelastic scattering tech- nique was used to study the temperature dependence of the magnetic excitations in iron from room temperature to well above the ferromagnetic ... high- quality 400 g 60 Ni single crystal which gave scattering intensities free from incoherent scattering and highly reduced inelastic scattering from phonons. The exper...

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... McEwen, in: Neutron Scattering, eds. K. Sköld and D.L. Price, Part C, vol. 23, p. 159 , Academic Press, London (1987). Paramagnetic and critical scattering 347 Fig. 9. (a) Contour plot of the magnetic ... of the vector at which the diffuse magnetic scattering is centered (from Chattopadhyay et al. [19]). (a) (b) Fig. 8. (a) Diffuse magnetic neutron scattering from MnS 2...

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... . . . . . . . 413 3.3.Polarization 415 3.4.Selectinganeutronpolarizationstate 417 3.5.Changinganeutron’spolarization 417 NEUTRON SCATTERING FROM MAGNETIC MATERIALS Edited by Tapan Chatterji Published ... gov- ern spin-dependent neutron reflection from magnetic materials, we can use what we have learned thus far about reflection from nonmagnetic media and the spin-dependent...

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