Magnetic scattering of x rays (invited)

Blume, M.

doi:10.1063/1.335023

Cited by 480 publications

(274 citation statements)

References 5 publications

Supporting

Mentioning

265

Contrasting

Unclassified

Order By: Relevance

“…For their derivation the quantity of interest is the transition rate probability W between the initial and final states of the excited atomic electrons, when they interact with light. The Hamiltonian of an atomic electron in a quantized electromagnetic field [169] can be split into contributions of the undisturbed electron system, free radiation field and interaction Hamiltonian, H = H 0 + H rad + H int , where…”

Section: Quantum Mechanical Descriptionmentioning

confidence: 99%

Antiferromagnetic dipolar ordering in[Co2MnGe∕V]Nmultilayers

et al. 2005

View full text Add to dashboard Cite

Section: Quantum Mechanical Descriptionmentioning

confidence: 99%

Antiferromagnetic dipolar ordering in[Co2MnGe∕V]Nmultilayers

et al. 2005

View full text Add to dashboard Cite

“…Consequently, a non-resonant magnetic X-ray diffraction (NRMXD) experiment was performed at beam line I16, Diamond Light Source, UK. This technique exploits the dependence of the NRMXD cross-section on the direction of the magnetic moment with respect to the incident and scattered directions of the light and the X-ray polarization [16]. To minimize the fluorescent background, the incident x-ray beam was tuned to 7.835 keV, well below the copper and niobium K absorption edges.…”

mentioning

confidence: 99%

Cu3Nb2O8: A Multiferroic with Chiral Coupling to the Crystal Structure

et al. 2011

View full text Add to dashboard Cite

By combining bulk properties, neutron diffraction and non-resonant X-ray diffraction measurements, we demonstrate that the new multiferroic Cu3Nb2O8 becomes polar simultaneously with the appearance of generalised helicoidal magnetic ordering. The electrical polarization is oriented perpendicularly to the common plane of rotation of the spins -an observation that cannot be reconciled with the "conventional" theory developed for cycloidal multiferroics. Our results are consistent with coupling between a macroscopic structural rotation, which is allowed in the paramagnetic group, and magnetically-induced structural chirality. [5] are cycloidal multiferroics, so called because their magnetic structures can be described as incommensurate circular (or elliptical) modulations with the wavevectors in the plane of rotation of the spins. In cycloidal multiferroics, the non-collinear magnetic configuration itself is established by the competition between nearest and next-nearest neighbor interactions. The coupling to the crystal structure occurs through the spin-orbit interaction, making it energetically favorable to develop local Dzyaloshinskii-Moriya (DM) vectors, associated with a local polarization. In simple, high-symmetry cases, the electrical polarization is perpendicular both to the magnetic propagation vector and to the normal to the plane of rotation of the spins, since the following formula holds [6]: P = λk m × (s 1 × s 2 ), where s 1 and s 2 are two adjacent spins along the propagation direction k m and λ is a coupling constant. In more complex, lower symmetry cases, the electrical polarization need not be perpendicular to the propagation vector, which, in turn, need not be contained in the plane of rotation of the spins (generic helicoidal structures). However, it is a strong prediction of the cycloidal multiferroics model that if all the spins rotate in a common plane, then the electrical polarization must be strictly contained within that plane.In this letter, we present a new multiferroic, with chemical formula Cu 3 Nb 2 O 8 and centrosymmetric triclinic symmetry (space group P1) in the paramagnetic phase. Using magnetic neutron powder diffraction, magnetic susceptibility, heat capacity, electrical polarization and non-resonant X-ray magnetic scattering measurements, we show that Cu 3 Nb 2 O 8 orders magnetically at T N ∼ 26 K, and develops an electrical polarization below a second magnetic transition at T 2 ∼ 24 K. In the polar phase below T 2 , a coplanar helicoidal magnetic structure is stabilized with propagation vector k m = (0.4876, 0.2813, 0.2029) in a general direction in reciprocal space. Strikingly, the electrical polarization in Cu 3 Nb 2 O 8 (with a magnitude of 17.8 µCm −2 ) is almost exactly perpendicular to the plane of rotation of the spins, in clear contradiction with the predictions of the cycloidal multiferroics model. We conclude that the electrical polarization in Cu 3 Nb 2 O 8 must arise through coupling of the chiral component of the magnetic structure with the crystal structure, ra...

show abstract

“…18,19,20 We summarize here the expression of the amplitude in a form suitable to the present calculation. The scattering geometry is shown in Fig.…”

Section: A Procedures Of Calculationmentioning

confidence: 99%

Mechanism of resonant x-ray magnetic scattering in NiO

Igarashi

Takahashi

2001

Phys. Rev. B

View full text Add to dashboard Cite

We study the resonant x-ray magnetic scattering (RXMS) around the K edge of Ni in the antiferromagnet NiO, by treating the 4p states of Ni as a band and the 3d states as localized states. We propose a mechanism that the 4p states are coupled to the magnetic order through the intra-atomic Coulomb interaction between the 4p and the 3d states and through the p-d mixing to the 3d states of neighboring Ni atoms. These couplings induce the orbital moment in the 4p band, and thereby give rise to the RXMS intensity at the K edge in the dipolar process. It is found that the spin-orbit interaction in the 4p band has negligibly small contribution to the RXMS intensity. The present model reproduces well the experimental spectra. We also discuss the azimuthal angle dependence of the intensity. 78.70.Ck, 71.20.Be, 75.50.Ee

show abstract

Magnetic scattering of x rays (invited)

Cited by 480 publications

References 5 publications

Antiferromagnetic dipolar ordering in[Co2MnGe∕V]Nmultilayers

Antiferromagnetic dipolar ordering in[Co2MnGe∕V]Nmultilayers

Cu3Nb2O8: A Multiferroic with Chiral Coupling to the Crystal Structure

Mechanism of resonant x-ray magnetic scattering in NiO

Contact Info

Product

Resources

About