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Several studies are conducted to explain the synthesis and the structural and magnetic properties of the various lanthanum doped multiferroic DyFe[O.sub.3]. The lattice parameters of the compounds are shown to increase linearly with an increasing La content.

Several studies are conducted to explain the different multiferroic properties of the various rare earth chromates. The compounds are shown to exhibit weak ferromagnetism at temperatures below the antiferromagnetic temperature.

A ferroelectric thin film of Aurivillius phase [K.sub.0.5][Bi.sub.4.5][Ti.sub.4][O.sub.15] (KBT) with a complex bismuth layer-structure is prepared by using the pulsed laser deposition method. The thin film grown on Pt/Ti/Si[O.sub.2]/Si substrate has shown a strong c-axis orientation and Pt/KBT/Pt capacitor has shown a maximum polarization.

The traditional solid state reaction method is used for preparing perovskite solid solution ceramics and ferroelectric and dielectric measurements have shown that these samples are relaxor type ferroelectric materials. The ac susceptibility measurement has showed that the peak position is dependent on frequency, thus indicating a glassy or relaxor type behavior and describing the 0.9Pb([Fe.sub.0.5][Nb.sub.0.5])[O.sub.3]-0.1PbTi[O.sub.3] to be a magnetoelectric relaxor material.

Rare earth element doped BiFe[O.sub.3] thin films are fabricated by using the pulsed laser deposition method and various targets made from different starting [Fe.sub.2][O.sub.3] and [Fe.sub.3][O.sub.4] iron source materials. The studies have shown that the [Fe.sup.2+] ion has played an important role in compensating for the charge imbalance and reducing current leakage, as well as enhancing the magnetic moment through the introduction of antiferrimagnetic ordering at [Fe.sup.2+] site.

The Al and C codoping effect on the structures and superconductivity in Mg[B.sub.2] is studied by using first-principles calculations. The studies have shown that the observed decrease in the high critical temperature for the codoped Mg[B.sub.2] is understood in terms of a band filling effect due to the electron doping by both Al and C.

The effect of the La doping on the structure and on the ferroelectric, dielectric and magnetic properties of BiFe[O.sub.3] is studied. Doping with La has increased the ferromagnetic moment, due to the broken cycloid spin structure caused by the changes in the crystalline structure.