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

摘要

Static and dynamical properties of Cu spins in the overdoped single-crystals 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 coexisting state of statically ordered Cu-spins and localized holes has been found 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 minus-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-dimensional 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 holes at x = 0.21 in the overdoped region of La2-xSrxCu1-yZnyO4. [References: 16]