We report here the unexpected observation of significant room-temperature ferromagnetism in a semiconductor doped with nonmagnetic impurities, Cu-doped TiO 2 thin films grown by pulsed laser deposition. The magnetic moment, calculated from the magnetization curves, resulted surprisingly large, about 1.5 B per Cu atom. A large magnetic moment was also obtained from ab initio calculations, but only if an oxygen vacancy in the nearest-neighbor shell of Cu was present. This result suggests that the role of oxygen vacancies is crucial for the appearance of ferromagnetism. The calculations also predict that Cu doping favors the formation of oxygen vacancies.

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Nonvolatile, electric-pulse-induced resistance switching is reported on S and Co doped ZnO thin films deposited on different substrates using magnetron sputtering and laser ablation. Two resistance states were obtained by applying voltage pulses of different polarity. The switching was observed regardless of the substrate, dopant species, or microstructure of the samples. In the Co doped ZnO samples, the two resistance states are remarkably stable and uniform.

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