Interaction of two different structural blocks in bi-system superconductors

The influence of the interaction between two structural blocks on supercond uctivity was studied by calculating the cohesive energy in 3 Bi-system supe rconducting phases [Bi2Sr2CuOy (2201), Bi2Sr2CaCu2Oy (2212), and Bi2Sr2Ca2C u3Oy (2223)] and the 2223 phase with different oxygen deficiency. The resul t indicates that if we consider the cell as the two blocks combined togethe r, a close relationship among the combinative energy between the two blocks (calculated from the cohesive energy of the unit cell), the value of T-c, a nd the number of the Cu-O planes in the Bi-system superconductors is establ ished. It suggests that the interaction between the two structural blocks, perovskite and rock salt, has a close relationship with the superconductivi ty.