No abstract

Vanadium dioxide thin films were deposited on c-cut sapphire and MgO(111) substrate using pulsed laser deposition method to investigate the effect of lattice misfit between the thin film and the substrate on the transition temperature of VO 2 thin film. All vanadium dioxide thin films showed heteroepitaxial growth with (002) preferred orientation. VO 2 /c-sapphire and VO 2 /MgO(111) had different transition temperatures, regardless of the thickness, orientation, and deposition conditions of the thin film. These results suggest that considering lattice mismatch between thin film and substrate is another promising option for controlling transition temperature of VO 2 thin films.

No abstract

No abstract

Ca3−xSrxCo4O9 with different compositions (x=0, 0.15, 0.3, and 0.45) were synthesized from stoichiometric mixtures of Co3O4, CaCO3, and SrCO3, and their unit-cell parameters were determined. The powders were mixed with silicon standard powder, and XRD patterns were collected and analyzed using TOPAS. The compounds were determined to be monoclinic with space group of P2. Unit-cell parameters changed from a=4.8329(3) Å, b=4.5727(1) Å, c=10.8360(4) Å, and β=98.093(7)° when x=0, to a=4.8432(1) Å, b=4.6100(3) Å, c=10.8668(3) Å, and β=98.110(5)° when x=0.3. An unidentified second phase was observed when x=0.45.