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The lattice defects and residual strain in layered perovskite [La.sub.2]Cu[O.sub.4+[delta]] (LCO) thin films, which are grown on LaSrAl[O.sub.4] and SrTi[O.sub.4] substrates, are investigated by using transmission electron microscopy and electron energy loss spectroscopy. The analysis has shown that the strain in LCO films on both the types of substrates are largely relaxed by the formation of misfit dislocation cores, although the small lattice mismatch is accommodated by elastic strain in the LCO film on the LaSrAl[O.sub.4] (LSAO) substrate.

The electronic structure of Pb(sub 1-x)La(sub x)TiO(sub 3) (PLT) compounds for x= 0 to 30 at. % of La is investigated by soft X-ray absorption near edge structure (XANES) at the Ti L(sub 3.2) and O k edges. The results show that although the distortion at the Ti site decreased as Pb atoms were replaced by La atoms, a perfect octahedral symmetry was not visible.

An glassy states is observed from the dc and ac susceptibility measurements in LaMn(sub 0.5)Fe(sub 0.5)O3. The large field-cooled effect and frequency-dependent results indicate a glassy state between T(sub g) and T(sub p') while the relaxation dynamics does not show cooperative relaxation without aging, suggesting the existence of noninteracting clusters of frozen spin.

X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy is used to study the surface properties of La0.7Sr0.3MnO3 thin films prepared by the channel-spark ablation technique. The findings show a surface layer consisting of SrO and SrCo3 of a few angstrom thick, which can significantly influence the spin injection properties at the interfacial region.

The effect of the content of La dissolved in Mg on the transmission of hydrogenated Mg-La films is examined. The studies have shown that with the increase in La:Mg atomic ratio, the transmission has decreased and the short wavelength limit of the transmission spectra has shifted towards the long wavelength side.