In this MRS Proceedings paper, we present a review of the floating zone growth process, and describe growth techniques as relevant to four selected families of current or continued interest in the area of condensed matter physics of highly correlated electron systems: Cuprate oxides (Bi 2 Sr 2 CaCu 2 O y ), Ruthenate oxides (Sr 2 RuO 4 ), Manganite oxides (La 1-x Sr x MnO 3 , La 2-2x Sr 1+2x Mn 2 O 7 , (RE)MnO 3 (RE=Rare Earth)) and Ferrite oxides (BiFeO 3 ). We also discuss our experiences with factors that tend to contribute to poor crystal growth, as relevant to experiments to probe correlated-electron physics in such crystals.

TbMnO3 is a multiferroic magnetoelectric material known to simultaneously exhibit antiferromagnetism below 40K and ferroelectricity below 28K in the same crystalline phase [1]. Following interesting results of Cu substitution in LaMn1-yCuyO3 [2, 3], we report a study of TbMn1-x CuxO3 (0 < x < 0.15). We describe here our results of crystal structure refinement, together with measurements of magnetic and dielectric properties in the temperature range 2 - 320 K, and magnetic field 0 - 9 T. We find no major changes in structure or symmetry upon substitution of Cu up to x = 0.15 in TbMn1-x CuxO3. Unlike LaMn1-yCuyO3, which exhibits ferromagnetism with very low values of y, we observe antiferromagnetism at x = 0.15. Our study of dielectric properties as a function of temperature suggests increased lossy behavior upon substitution of Cu at the Mn site. In our temperature dependent studies of tan δ at 1 kHz, we observe a well-defined step-like feature near 120K in both pure and substituted samples, possibly ascribable to a change in carrier mobility, or a dielectric-relaxation process mediated by ordered oxygen vacancies [4, 5], which we will continue to study.

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Spectroscopic studies are rarely performed at very high temperature, especially when combined with light from a synchrotron source. Demanding conditions of maintaining ultrahigh vacuum (UHV) during heating, together with the typically brief access to beam time at multiuser synchrotron end stations, may contribute to some of the reasons for the difficulty of such experiments. Consequently, a large number of materials with interesting properties and industrial applications at high temperature remain unexplored. The authors describe here a simple portable sample mount assembly that can be easily utilized at a beamline, with potential utility for a variety of spectroscopic measurements requiring elevated temperatures and an UHV environment. In the specific application described here, the authors use a resistive cartridge heater interfaced with a standard manipulator previously designed for cooling by liquid nitrogen with an UHV chamber and a cylindrical mirror analyzer for x-ray photoemission spectroscopy (XPS) [also known as electron spectroscopy for chemical analysis (ESCA)] at the Synchrotron Radiation Center in Stoughton, WI. The heater cartridge required only modest power to reach target temperatures using an open-loop temperature control. Finally, the authors describe the measurements of XPS (ESCA) and total-electron yield x-ray absorption spectroscopy on nanopowders and on single crystals grown by them. They emphasize the simplicity of the setup, which they believe would be of interest to groups performing measurements at large facilities, where access and time are both limited.

Multiferroic materials, i.e. materials that possess more than one ferroic order (ferro-or antiferromagnetic, ferroelectric, ferroelastic, and so on) are of great current interest because they provide means to combine electronic and magnetic device functions into a single class of materials. One approach, in the search for new materials, has been to substitute Fe into a ferroelectric lattice, like the PbTiO 3 perovskite structure, in an attempt to generate multiferroic coupling. Among the many questions, in ongoing efforts to understand multiferroic behavior, is whether multiple ferroic order is a result of the subtle effects of the coexistence of two types of structural phases (not necessarily "chemical" phases) fueling intense structural investigations at the micro-and nano-level. This structural study focuses on PbTi 0.5 Fe 0.5 O 3 (PTFO), a material reported to display room temperature magnetoelectric behavior1 .The present HRTEM study is performed using a Hitachi H9000NAR instrument operated at 300keV. It is part of systematic synthesis and multi-technique characterization of PbTi 1-x Fe x O 3 (PTFO) in the range 0 type orientations. The minority phase has straight fringes with some lattice spacings that coincide with the majority phase, but also spacings that are unique. This is similar to a rare tetragonal form of PbTiO 3 with unit cell parameters of a=b=1.236nm and c=1.4534nm. 3 The contrast of the dominant phase appears complicated. After Fourier filtering (inset in Fig. 4a) and superposition of a regular grid (Fig 4b), it becomes apparent that even the individual nanocrystals are composed of sub-domains. We find that the shift of the lattice fringes between the nei...