Memory Effects in the Charge Response of Lightly Doped La_(2-x)Sr_(x)CuO₄

The in-plane magnetoresistance (MR) of a single crystal La_{1.97}Sr_{0.03}CuO_{4} has been studied at low temperatures T using several experimental protocols. At T well below the spin-glass transition temperature, the MR becomes positive and exhibits several glassy features, such as history dependence, memory and hysteresis. These observations are qualitatively similar to the previously reported behavior of the out-of-plane resistance. The results suggest that the memory effects in the MR are related to the onset of glassiness in the dynamics of doped holes.