A technique for measuring the 3-dimensional to 2-dimensional conductivity change of YBCO superconductors at the normal-to-superconducting phase change

摘要: It is well known that conduction in YBa2Cu3O7 (YBCO) by means of copper “planes” and “chains,” where planes chains describe the degree bonding between oxygen. Changes conductivity versus temperature have been used to show YBCO normal state 3-dimensional, while approaching onset superconducting first 2-dimensional then 3-dimensional. We found another method monitor this 2-to-3 transition. Using square samples, measuring voltage at each corner caused a current applied opposite corners, one can find conductivities along x-axis y-axis. The ratio these unity for homogeneous samples state. However, transition state, changes. examine change as function sample purity, history, exposure an external magnetic field. Our data are consistent with reported literature, they suggest existence deep which only observable application