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The magnetic frustration effects in the La(sub 1-x)Ca(sub x)MnO3 (x=0.2,0.3) single crystals from dc and ac susceptibility measurements are investigated. It was seen that the magnetic transition around 100 K involving probably charge-ordered phase was affected by the frequency and the spin dynamics of La(sub 0.8)Ca(sub 0,2)MnO3 that changed drastically at high frequencies (approximately at 10 KHz).

(001) substrate as a function of film thickness (50 and 100 nm) and oxygen content (optimum and reduced) is investigated using magnetic force microscopy. The domain nucleation and growth takes place by discrete reorientation of regions that have diameters similar to the final domain width.

Low-angle inelastic neutron scattering was used to study the temperature and wave vector dependence of the spin waves in La(sub 0.67)Ca(sub 0.33)MnO(sub 3) perovskite-based colossal magnetoresistance material. Detailed neutron measurements of the order parameter in zero applied field showed a similar first-order like transition.

Ultrafine La(sub 0.7)Ca(sub 0.3)MnO(sub z) powders with controlled oxygen stoichiometry are synthesized by mechanical alloying at ambient temperature. These observations are discussed in terms of magnetic disorder resulting from defects induced by high-energy milling and surface effects dominant in small crystals.

The influence of nickel doping in a series of n-type CoSb3 skutterudite materials partially filled with Ca is investigated. The electrical resistivity, thermopower, and thermal conductivity is measured in the 300-800 K temperature range on Ca(sub y)Co(sub 1-x)Ni(sub x)Sb(sub 12) compounds prepared by a powder metallurgy route.

The Ca2N work function and surface energy for the (0001) and the (1000) surface is described. Ca2N is a promising metal for replacing calcium as cathode material for polymer light emitting diode devices.

Organic molecules and nanoparticles embedded in inorganic crystalline lattices are studied to add different properties and functions to composite materials. Doping CaCO(sub 3) with nanoparticles enhances ultraviolet absorption, which is suggested for use as UV absorbers.

The structure changes and electrical properties in Ca(sub 4)Mn(sub 3)O(sub 10) under high pressure at room temperature are studied using energy-dispersive x-ray diffraction with synchrotron radiation and resistance and capacitance measurements. The steep drop of resistance and the abrupt rise of capacitance observed in the measurements are caused by the compression of the rocksalt layers in the structure, thereby resulting in the band structure changes.

Current-voltage (I-V) characteristics of Pr0.5Sr0.3Ca0.2MnO3 are measured at different temperatures and different fields. The enhancement of MR ratio evidences the existence of an intermediate state between the charge ordering state and the charge ordering breakdown state.