We report distinct optical/electrical properties inherent to build-in nanostructures in transparent oxide based materials, oxychalcogenides LaCuOS and LaCuOSe having naturally formed multi-quantum well structures and 12CaO·7Al2 O3 (C12A7) with a unique nanoporous structure. LaCuOSe doped with Mg ions exhibit degenerative p-type conduction presumable due to "modulation doping mechanism" with a high mobility of 4.0 cm2 V-1 s-1 even at high hole concentration (∼2×1020 cm-3). The room temperature exciton, having a large binding energy (∼50 meV) due to the confinement effect of carriers in the CuS or CuSe layer, induces a large optical nonlinearity at room temperature (RT) (χ(3) = 2-4×10-9 esu) near the absorption band. The H- ion entrapped in nanosize cages in C12A7 lattice causes an persistent conversion at RT from an electric insulator (<10-10 S cm-1) to a semiconductor (0.3-100 S cm-1) by capturing electrons photo-ionized from H- ions in the cages. This is a first electronic conductor based on main group light metal oxides.
|Number of pages||7|
|Journal||Journal of Photochemistry and Photobiology A: Chemistry|
|Publication status||Published - Aug 12 2004|
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Physics and Astronomy(all)