mu SR study on the Cu-spin state in La2-xSrxCu1-yZnyO4

Static and dynamical properties of Cu spins in the overdoped single-crystal s of La2-xSrxCu1-yZnyO4 have been investigated by the muon-spin-relaxation (mu SR) method. In the Zn-substituted single-crystal with x = 0.21 and y = 0.01, where the high-T-c superconductivity is anomalously suppressed, a coe xisting state of statically ordered Cu-spins and localized holes has been f ound at low temperatures below about 2 K. The dynamical depolarization rate of the muon spin at 3.0 K has been found to be nearly proportional to minu s-root-square of the external magnetic-field applied along the initial muon -spin polarization. This field-dependence can be explained by assuming the existence of an excited state of the Cu spins diffusing in a one-dimensiona l direction. The present study suggests a high possibility of the existence of a new one-dimensional stripe ordered state of the Cu spins and doped ho les at x = 0.21 in the overdoped region of La2-xSrxCu1-yZnyO4.