Anisotropic Magnetoresistance in Lightly Doped La_(2-x)Sr_(x)CuO₄: Impact of Anti-Phase Domain Boundaries on the Electron Transport

Detailed behavior of the magnetoresistance (MR) is studied in lightly doped antiferromagnetic La_{1.99}Sr_{0.01}CuO_{4}, where, thanks to the weak ferromagnetic moment due to spin canting, the antiferromagnetic (AF) domain structure can be manipulated by the magnetic field. The MR behavior demonstrates that CuO_2 planes indeed contain anti-phase AF domain boundaries in which charges are confined, forming anti-phase stripes. The data suggest that a high magnetic field turns the anti-phase stripes into in-phase stripes, and the latter appear to give better conduction than the former, which challenges the notion that the anti-phase character of stripes facilitates charge motion.