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Hexagonal rare-earth manganese oxide YMnO3 thin films were prepared on yttria-stabilized zirconia (111) substrates by metal organic decomposition method. The crystallinity and morphology of YMnO3 thin films crystallized at various temperatures were examined by X-ray diffraction and atomic force microscopy measurements, respectively. Single phase YMnO3 was obtained for the sample prepared by annealing temperatures of 950 °C. AFM analysis revealed that a smooth surface with a roughness of 0.15 nm was achieved for YMnO3 thin film annealed at 950 °C and 1000 °C, while three-dimensional growth for other samples prepared at 750–900 °C, 1050 °C, and 1100 °C. A narrow band at 1.6 eV and a broad band at 5 eV due to electronic transitions in the manganese and oxygen bands were observed in an absorption spectrum.

EuTe/PbTe double-well superlattices with two kinds of PbTe quantum wells separated by monolayer EuTe were prepared on KCl(100) substrates by hot wall epitaxy. Strong intersubband absorptions as high as 2000 cm-1 in absorption coefficient were observed for n-type samples with a carrier concentration as high as 3×1018 cm-3 at normal incidence. The absorption was caused through the modulation of quantum-well potential along superlattice direction at L-point of the Brillouin zone. Temperature dependence of the optical transmission properties was also measured and the absorption peak showed a large tunability of 0.9 cm-1 K-1 caused by large temperature dependence of effective masses in PbTe.