X-ray and neutron scattering

Abstract:

We have applied the technique of polarised neutron reflectometry (PNR) to investigate the magnetic held profile near the surface of YBa2Cu3O7 films at 4.3 K. The samples comprised 700-1400 nm of c-axis oriented, single crystal YBa2Cu3O7 deposited by laser ablation on SrTiO3 substrates. The measurements were carried out on the CRISP reflectometer at the ISIS facility.The PNR technique measures the magnetic induction profile perpendicular to the surface, and so in our case the decay of flux in the c-direction was measured with a held applied parallel to the ab plane. We present preliminary data for the polarised and unpolarised reflectivity (C) 1998 Elsevier Science B.V. All rights reserved.

Abstract:

We have used polarised neutron diffraction to measure the magnetisation density induced by an applied magnetic field in single-crystal PrBa2Cu3O6.24. A modified maximum entropy method was employed to invert the diffraction data. The images thus produced show evidence of Pr on the Be site, distortions of the Pr ion, and other interesting features. (C) 1998 Elsevier Science B.V. All rights reserved.