Magnetic and superconducting phase diagram of electron-doped Pr${}_{1-x}$LaCe${}_x$CuO${}_4$

We have investigated the magnetism and the superconductivity of an electron-doped Pr${}_{1-x}$LaCe${}_x$CuO${}_4$ (PLCCO) using single crystal and powder samples by means of zero-field muon spin rotation/relaxation (ZF-$\mu$SR) and magnetic susceptibility measurements. Muon spin rotation corresponding to antiferromagnetic (AF) order was observed in the sample with 0.04$\le${\it x}$\le$0.11. Changes in magnetic properties of Cu spins upon Ce doping were revealed because the effect of the rare earth moment was negligible. Bulk superconductivity was identified in a wide Ce concentration range of 0.09$\le${\it x}$\le$0.20 with a maximum transition temperature of 26 K. At low temperatures, the superconducting (SC) phase abruptly appears by doping with linking quick destroy of the AF ordered phase at {\it x}$\sim$0.09, indicating the competitive relation between two phases.