mu SR study of impurity effects on the Cu-spin fluctuations in the overdoped regime of La2-xSrxCu1-yZnyO4

摘要

Zero-field muon-spin-relaxation measurements have been carried out for La2-xSrxCu1-xZnyO4 (LSCO) with y = 0-0. 10 in the overdoped regime up to x = 0.30, in order to investigate whether the dynamical stripe correlations are pinned and stabilized even for the overdoped LSCO or not. It has been found that the Zn-induced slowing down of the Cu-spin fluctuations is weakened with increasing x but takes place in the overdoped regime and disappears at x = 0.30. This suggests that the stripe-pinning model holds good in the whole superconducting regime of LSCO and that there is no quantum critical point at x similar to 0.19. (c) 2007 Elsevier B.V. All rights reserved.