Resonant X-ray diffraction on manganites

Resonant soft X-ray diffraction - in extremis.

The use of softer-energy X-rays produced by synchrotron radiation for diffraction is an area of current interest. In this paper, experiments exploiting resonant scattering at the L absorption edges of 3d transition metal elements are reported. Such energies, typically 500-1000 eV, are at the extreme limit of soft X-ray diffraction where absorption effects are so severe that the sample and diffr...

Resonant X-ray Diffraction: basic theoretical principles

We present the main steps governing the theory of resonant x-ray diffraction (RXD). We focus on the derivation of the anomalous scattering amplitude from perturbation theory and starting from the low-energy expansion of the Dirac Hamiltonian. We give the main ingredients of the multipolar expansion in term of electric and magnetic transitions. We also show the expansion in terms of scattering t...

Soft X-ray resonant magnetic diffraction.

We have conducted the first soft x-ray diffraction experiments from a bulk single crystal, studying the bilayer manganite La2-2xSr1+2xMn2O7 with x=0.475 in which we were able to access the (002) Bragg reflection using soft x rays. The Bragg reflection displays a strong resonant enhancement at the L(III) and L(II) manganese absorption edges. We demonstrate that the resonant enhancement of the ma...

Resonant X-ray Scattering and Multiple Beam Diffraction in LaMnO3

Fig 1: The solid points give the location and shape of the (1 0 –4) resonant reflection in orthorhombic LaMnO3. Open circles display Mn Kα fluorescence from the same sample on a common energy scale. The vertical scale is arbitrary and the lines are guides to the eye. In conventional X-ray diffraction the beam scatters from all electrons in the unit cell, but in resonant diffraction at a forbidd...

Birefringence and polarization rotation in resonant x-ray diffraction