Uniaxial linear resistivity of superconducting La1.905Ba0.095CuO4 induced by an external magnetic field

We present an experimental study of the anisotropic resistivity of superconducting La2-xBaxCuO4 with x = 0.095 and transition temperature T-c = 32 K. In a magnetic field perpendicular to the CuO2 layers H-perpendicular to, we observe that the resistivity perpendicular to the layers rho(perpendicular to) becomes finite at a temperature consistent with previous studies on very similar materials; however, the onset of finite parallel resistivity rho(parallel to) occurs at a much higher temperature. This behavior contradicts conventional theory, which predicts that rho(perpendicular to) and rho(parallel to) should become finite at the same temperature. Voltage versus current measurements near the threshold of voltage detectability indicate linear behavior perpendicular to the layers, becoming nonlinear at higher currents, while the behavior is nonlinear from the onset parallel to the layers. These results, in the presence of moderate H-perpendicular to, appear consistent with superconducting order parallel to the layers with voltage fluctuations between the layers due to thermal noise. In search of uncommon effects that might help to explain this behavior, we have performed diffraction measurements that provide evidence for H-perpendicular to-induced charge-and spin-stripe order. The field-induced decoupling of superconducting layers is similar to the decoupled phase observed previously in La2-xBaxCuO4 with x = 1/8 in zero field.