A study of the in-plane resistance noise on a high quality single crystal of La_{ 1.97}Sr_{ 0.03}CuO_{ 4} deep inside the spin-glass phase reveals the onset of non-Gaussianity and the insensitivity of the noise to the in-plane magnetic field. The results indicate that the charge dynamics becomes increasingly slow and correlated as temperature T -> 0. The analysis of the higher order noise statistics provides evidence for the existence of a collective ground state of charge clusters, which seem to coexist with charge-poor antiferromagnetic domains that are frozen at such low T.
Categories: cond-mat.str-el