  High-Tc Cu oxides consist of the alternating stack of the superconductive
CuO2 layer and the block layer, such as Bi2Sr2O4 or La2-xSrxO2. By changing the
block layer, we can change their physical properties, such as transition
temperature Tc. The thermoelectric Co oxides have a similar layered structure
composed of the conductive CoO2 layer and the blocking layer. Thus, we propose
that their thremoelectric properties can be finely tuned by modifying the block
layer.
