Layered Ultrathin Coherent Structures (LUCS) made up of transition metals Nb and Ti exhibit peculiar electrical conduction properties, which reflect the energy band charateri-stics of these artificial superlattices such that there is a transition from metallic to semiconducting or semi-metallic properties with decreasing superlattice period. Owing to the supe-rlattice modulation, there are two catagories of electronic states in LUCS: extended states and strongly localized states in the direction of modulation. Electrons in these two kinds of states have very different effective masses along the modulation direction. We have considered separately the contributions of the two kinds of electronic states, and have obtained the resistivity and its temperature coefficient which show variations with the inverse superlattice period in accordance with measurements.
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