Mo-and Mn-doped VO 2 thin films have been grown on c-cut sapphire substrates by the magnetron co-sputtering technique. The effects of Mo and Mn doping on the structure and metal-insulator transition of the doped VO 2 thin films were studied. An enlargement of the out-of-plane lattice constant of the film caused by Mo doping was observed. As expected, the transition temperature (T MI) is reduced by Mo doping. However, the valence of the Mo ions doped in the VO 2 films is determined by X-ray photoelectron spectroscopy to be 6+ on the surface, but 4+ and 3+ in the bulk part of the films. The reduction in T MI observed in this study is attributed to the variation in the band structure resulting from the incorporation of Mo 4+ into the VO 2 lattice. The optical transmission is remarkably enhanced by low-concentration Mo doping and then monotonically decreases with increasing Mo content. On the other hand, the out-of-plane lattice constant and T MI are not affected by Mn doping. The transmission is enhanced and then monotonically increases with increasing Mn concentration. The thermochromism of doped films is suppressed by Mo and Mn doping.

We employ dissipative particle dynamics (DPD) to examine the effects of composition and interaction parameter on the resulting phase behavior of ABC star copolymers. Here, we assume that the interaction parameters among the three components are equal. When the three components have comparable volume fractions, our DPD results illustrate that the unique formation of various types of three-phase separated polygonal cylinders is mainly dominated by the composition but not influenced by the interaction parameter. In contrast, when two of the three components are minor, the resulting morphology type is greatly influenced by the interaction parameter. Generally speaking, with an increase in the interaction parameter, the two minority components first act like one component and the system forms a one-length-scale ordered microstructure. Then a further segregation between the two minority components within the large-length-scale phase can be induced as the interaction parameter keeps increasing. In general, our DPD results, a systematic study of the morphological transition behavior obtained by varying the interaction parameter and composition, bridge the gap between the previous theoretical results in the strong and weak segregation regimes via Monte Carlo and two-dimensional self-consistent mean-field methods, respectively.

Room-temperature ferromagnetism was observed in Mn and Zn codoped SnO2 films grown on c-cut sapphires by using pulsed laser deposition technique. The valence of Mn ions in the codoped films is determined to be 2+ from x-ray absorption near edge spectroscopy. Moreover, the ferromagnetism is affected by the carrier concentration of the films. This result is consistent with the carrier-mediated model.

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Amorphous InGaZnO4 (a-IGZO) films doped with various concentrations of Mn have been fabricated by using pulsed-laser deposition technique. Optical, electrical, and magnetic properties of the prepared Mn-doped a-IGZO films were investigated. The resistivity, carrier concentration, and carrier mobility of the a-IGZO films were found to be, respectively, increased, decreased, and enhanced by Mn doping. Moreover, the optical transmission is slightly increased in the visible range and the optical band gaps are not affected in the Mn-doped films. Room-temperature ferromagnetism has been observed in the field-dependent magnetization measurements.