Superlattices quantum size effect

The electronic properties of the new superlattice materials help to shed light on some major fundamental questions in amorphous semiconductors. Quantum size effects in the case of crystalline superlattices raise the lowest allowed electron and hole energy levels and give rise to a density of states that increases in discrete steps. This structure in the density of states is reflected in... 

Conjugated polymer superlattices and porphyrin arrays connected with molecular wires are superstructured materials, which exhibit unique optical and photonic functions. The former shows a shift in photoluminescence to higher energy which is interpreted as a quantum size effect. The latter class of materials exhibits photoconductivity by a hole carrier mechanism and photoinformation storage by a localized excitation mechanism. The syntheses of these two classes of materials are described. 

Recently, much attention has been paid to the importance of the quantum function realized by micro- and mesoscopically controlled semiconductor heterostructures. Conducting polymer heterolayers, leading to a conducting polymer superlattice exhibiting quantum size effects, should take an important place in both novel electronic and optical devices. 

The direction of modem device fabrication, is toward production of complex structures (including those with the elements of HTSC) with characteristic dimensions in the micro and nano ranges [426-428]. These include superlattices [429,430], and other nanocompositions [431,432], particularly those which contain HTSC/HTSC junctions (two HTSC materials with different properties), as well as HTSC/metal, HTSC/semiconductor, and HTSC/dielectric junctions. These structures form the basis of modem electronics, and exhibit different size-dependent quantum effects. 

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