Magnetic inhomogeneity on a triangular lattice: the magnetic-exchange versus the elastic energy and the role of disorder.

Inhomogeneity in the ground state is an intriguing, emergent phenomenon in magnetism. Recently, it has been observed in the magnetostructural channel of the geometrically frustrated α-NaMnO2, for the first time in the absence of active charge degrees of freedom. Here we report an in-depth numerical and local-probe experimental study of the isostructural sister compound CuMnO2 that emphasizes and provides an explanation for the crucial differences between the two systems.

Frustration-induced nanometre-scale inhomogeneity in a triangular antiferromagnet.

Phase inhomogeneity of otherwise chemically homogenous electronic systems is an essential ingredient leading to fascinating functional properties, such as high-Tc superconductivity in cuprates, colossal magnetoresistance in manganites and giant electrostriction in relaxors. In these materials distinct phases compete and can coexist owing to intertwined ordered parameters. Charge degrees of freedom play a fundamental role, although phase-separated ground states have been envisioned theoretically also for pure spin systems with geometrical frustration that serves as a source of phase competition.

One-dimensional magnetic fluctuations in the spin-2 triangular lattice alpha-NaMnO2.

The S=2 anisotropic triangular lattice alpha-NaMnO2 is studied by neutron inelastic scattering. Antiferromagnetic order occurs at T< or =45 K with opening of a spin gap. The spectral weight of the magnetic dynamics above the gap (Delta approximately equal to 7.

Nanostructured bioceramics for maxillofacial applications.

Biomaterials science and technology have been expanding tremendously the recent years. The results of this evolution are obvious in maxillofacial applications especially with the contemporary development of Nanotechnology. Among biomaterials, bioceramics possess a specific field due to various interactions with the biological tissues.

Microstructure effect on the properties of a commercial low-fusing dental porcelain.

The aim of this study was to investigate the effect of firing cycle on a dental porcelain microstructure in order to correlate microstructure changes with mechanical and thermal properties. A commercial low-fusing dental porcelain powder (Omega 900, Vita) was investigated for this purpose. The powder was treated at different temperatures in the range 750-1000 degrees C.