μSR Study in La 2−x Sr x Cu 1−y Zn y O 4 with x≃l/8

In order to investigate the magnetic state around hole density 1/8 in LaSr-214, μSR experiments were carried out for the samples of Zn-free La 2−x Sr x CuO 4 and Zn-doped La 2−x Sr x Cu 1−y Zn y O 4. For Zn-free samples, μ-spin rotation was observed in x=0.115 below about T r =10K, implying magnetic order, but not observed in x=0.125. On the other hand, Zn-doping brought about μ-spin rotation in x=0.125 sample below T r =7K, implying growth of magnetic order but decreased T r in x=0.115, meaning destruction of magnetic order. This indicates that Zn-doping pins dynamical spin modulation, resulting in static magnetic order in x=0.125 sample.