Structural phase transition nomenclature -: Report of an IUCr working group on phase transition nomenclature

ACTA CRYSTALLOGRAPHICA SECTION A 54 (1998) 1028-1033

Authors:

JC Tolédano, AM Glazer, T Hahn, E Parthé, RS Roth, RS Berry, R Metselaar, SC Abrahams

Improvements to the polarised-neutron reflectometer CRISP

PHYSICA B 241 (1997) 148-150

Authors:

V Nunez, AT Boothroyd, J Reynolds, J Penfold, S Langridge, DG Bucknall, P Boni, D Clemens, MS Kumar

Abstract:

The reflectometer CRISP at ISIS is being upgraded to expand its capabilities in the polarised-beam mode. The polarisers are being replaced by Fe-Co-V:TiNx supermirrors to give a higher incident flux and a two-times larger dynamic range. The flippers have also been redesigned to give higher flipping efficiencies over larger beam sizes and wavelength ranges. The improvements are described and compared to the current instrument performance. (C) 1998 Elsevier Science B.V. All rights reserved.

Neutron time-of-flight measurements of diffuse scattering

Physica B Condensed Matter Elsevier 241 (1997) 201-203

Authors:

DA Keen, MJ Harris, WIF David

Polarised neutron reflectometry studies of flux penetration in superconducting Nb

PHYSICA B 241 (1997) 1104-1106

Authors:

JM Reynolds, V Nunez, AT Boothroyd, R Somekh, DG Bucknall, S Langridge

Abstract:

We have applied the technique of polarised neutron reflectometry (PNR) to investigate the magnetic held penetration in different superconducting phases of Nb, namely the Meissner state (H < H-c1), the mixed state (H-c1 < H < H-c2) and the surface superconductivity state (H-c2 < H < H-c3) around 4 K. The sample was a sputtered him of Nb with a 3 mu m thickness on a 5 mm Si crystal substrate. The measurements were carried out on the CRISP reflectometer at the ISIS facility, with field strengths between 400 and 4500 Oe. We present preliminary data for the spin-dependent reflectivity as a function of applied field. (C) 1998 Elsevier Science B.V. All rights reserved.

R-Cu magnetic coupling in RBa2Cu3O6+x, with particular reference to PrBa2Cu3O6+x

PHYSICA B 241 (1997) 792-794

Abstract:

In this paper I enumerate the possible magnetic structures that may be observed in RBa2Cu3O6+x compounds when a bilinear coupling exists between the R and Cu magnetic moments. I discuss the implications of this coupling for local relaxation probes at the R site. (C) 1998 Elsevier Science B.V. All rights reserved.