Three-dimensional spin fluctuations in Na0.75CoO2

Physical Review Letters 94 (2005) article 157206 4pp

Authors:

LM Helme, AT Boothroyd, R Coldea, D Prabhakaran, DA Tennant, A Hiess, J Kulda

Probing orbital order with soft x-rays: The case of the manganites

New Journal of Physics 7 (2005)

Authors:

SB Wilkins, TAW Beale, PD Hatton, JA Purton, P Bencok, D Prabhakaran, AT Boothroyd

Abstract:

We have investigated the orbital and magnetic correlations of the manganese sub-lattice in the archetypical half-doped manganite La 0.5Sr 1.5MnO 4 using the enhanced sensitivity of resonant soft x-ray diffraction at the Mn L edges. We have separately measured the energy dependence of the scattered intensity from both the (1/4, 1/4, 0) and (1/4,1/4,1/2) reflections indicative of the long-range correlations of orbital and magnetic order respectively. Measurements of the integrated intensity of the different features in the resonant energy spectrum show the different origins of the orbital correlations and their variation with temperature. The results also give evidence for a strong coupling between the orbital and spin degrees of freedom. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

Bulk single crystal growth and magnetic studies of La1-xSrxCoO3+δ

Journal of Crystal Growth 275:1-2 (2005)

Authors:

D Prabhakaran, AT Boothroyd, FR Wondre, TJ Prior

Abstract:

We report the growth of single crystals of La1-xSrxCoO3+δ (x=0.0 and 0.33) by the floating-zone technique in an image furnace under high pressure (7-9 atm). Single crystals of diameter 10 mm and length 100 mm have been obtained. The phase purity, composition, oxygen stochiometry and quality of the crystals were analysed. We discuss the effect on the crystal growth of the growth atmosphere. We also present some of the magnetization data for the grown crystals. © 2004 Elsevier B.V. All rights reserved.

Bulk single crystal growth and magnetic studies of La1−xSrxCoO3+δ

Journal of Crystal Growth Elsevier 275 (2005) e827-e832

Authors:

D Prabhakaran, AT Boothroyd, FR Wondre, TJ Prior

Abstract:

We report the growth of single crystals of La1−xSrxCoO3+δ (x=0.0 and 0.33) by the floating-zone technique in an image furnace under high pressure (7–9 atm). Single crystals of diameter 10 mm and length 100 mm have been obtained. The phase purity, composition, oxygen stochiometry and quality of the crystals were analysed. We discuss the effect on the crystal growth of the growth atmosphere. We also present some of the magnetization data for the grown crystals.

Progress in NaxCoO2 Single Crystal Growth

Chapter in Frontiers in Superconducting Materials, Springer-Verlag (2005) 683-695

Authors:

D Prabhakaran, AT Boothroyd