Tunable resistivity of correlated VO(A) and VO(B) via tungsten doping.

Applications of correlated vanadium dioxides VO(A) and VO(B) in electrical devices are limited due to the lack of effective methods for tuning their fundamental properties. We find that the resistivity of VO(A) and VO(B) is widely tunable by doping them with tungsten ions. When x < 0.

Spectroscopic Studies on the Metal-Insulator Transition Mechanism in Correlated Materials.

The metal-insulator transition (MIT) in correlated materials is a novel phenomenon that accompanies a large change in resistivity, often many orders of magnitude. It is important in its own right but its switching behavior in resistivity can be useful for device applications. From the material physics point of view, the starting point of the research on the MIT should be to understand the microscopic mechanism.

Dimensionality control of d-orbital occupation in oxide superlattices.

Manipulating the orbital state in a strongly correlated electron system is of fundamental and technological importance for exploring and developing novel electronic phases. Here, we report an unambiguous demonstration of orbital occupancy control between t2g and eg multiplets in quasi-two-dimensional transition metal oxide superlattices (SLs) composed of a Mott insulator LaCoO3 and a band insulator LaAlO3. As the LaCoO3 sublayer thickness approaches its fundamental limit (i.