Diverging resistivity anisotropy with decreasing temperature in 60-K YBa2Cu2O7y

Abstract
The in-plane resistivity ρab of 60-K YBa2 Cu3 O7y is equal to (340±30) μΩ cm at 290 K and varies approximately linearly with temperature T. The anisotropy ρc/ρab increases from ∼100 to 2000 as T decreases from 290 to 80 K. In the four crystals studied ρc is observed to increase monotonically with decreasing T. This is an intrinsic property of the normal state which has not been explained by conventional transport theory.