ChemInform Abstract: Magnetic Coulomb Phase in the Spin Ice Ho2Ti2O7.

ChemInform Wiley 40:51 (2009) no-no

Authors:

T Fennell, PP Deen, AR Wildes, K Schmalzl, D Prabhakaran, AT Boothroyd, RJ Aldus, DF McMorrow, ST Bramwell

Preface: Symposium HH

Materials Research Society Symposium Proceedings 1184 (2009)

Authors:

F Bridges, DA Keen, I Levin, T Proffen

Nature of the magnetic order and origin of induced ferroelectricity in TbMnO3.

Phys Rev Lett 103:20 (2009) 207602

Authors:

SB Wilkins, TR Forrest, TAW Beale, SR Bland, HC Walker, D Mannix, F Yakhou, D Prabhakaran, AT Boothroyd, JP Hill, PD Hatton, DF McMorrow

Abstract:

The magnetic structures which endow TbMnO(3) with its multiferroic properties have been reassessed on the basis of a comprehensive soft x-ray resonant scattering (XRS) study. The selectivity of XRS facilitated separation of the various contributions (Mn L(2) edge, Mn 3d moments; Tb M(4) edge, Tb 4f moments), while its variation with azimuth provided information on the moment direction of distinct Fourier components. When the data are combined with a detailed group theory analysis, a new picture emerges of the ferroelectric transition at 28 K. Instead of being driven by the transition from a collinear to a noncollinear magnetic structure, as has previously been supposed, it is shown to occur between two noncollinear structures.

Nature of the magnetic order and origin of induced ferroelectricity in TbMnO3

Physical Review Letters 103:20 (2009)

Authors:

SB Wilkins, TR Forrest, TAW Beale, SR Bland, HC Walker, D Mannix, F Yakhou, D Prabhakaran, AT Boothroyd, JP Hill, PD Hatton, DF McMorrow

Abstract:

The magnetic structures which endow TbMnO3 with its multiferroic properties have been reassessed on the basis of a comprehensive soft x-ray resonant scattering (XRS) study. The selectivity of XRS facilitated separation of the various contributions (Mn L2 edge, Mn 3d moments; Tb M4 edge, Tb 4f moments), while its variation with azimuth provided information on the moment direction of distinct Fourier components. When the data are combined with a detailed group theory analysis, a new picture emerges of the ferroelectric transition at 28 K. Instead of being driven by the transition from a collinear to a noncollinear magnetic structure, as has previously been supposed, it is shown to occur between two noncollinear structures. © 2009 The American Physical Society.

High-resolution hard x-ray photoemission investigation of La 2-2xSr 1+2xMn 2O 7 (0.30≤x<0.50): Microscopic phase separation and surface electronic structure of a bilayer colossal magnetoresistance manganite

Physical Review B - Condensed Matter and Materials Physics 80:20 (2009)

Authors:

S De Jong, F Massee, Y Huang, M Gorgoi, F Schaefers, J Fink, AT Boothroyd, D Prabhakaran, JB Goedkoop, MS Golden

Abstract:

Photoemission data taken with hard x-ray radiation on cleaved single crystals of the bilayered, colossal magnetoresistant manganite La 2-2xSr 1+2xMn 2O 7 (LSMO) with 0.30≤x<0.50 are presented. Making use of the increased bulk sensitivity upon hard x-ray excitation it is shown that the core-level footprint of the electronic structure of the LSMO cleavage surface is identical to that of the bulk. Furthermore, by comparing the core-level shift of the different elements as a function of doping level x, it is shown that microscopic phase separation is unlikely to occur for this particular manganite well above the Curie temperature. © 2009 The American Physical Society.