Magnetic and superconducting phase diagram in oxybromite cuprate Ca2-xNaxCuO2Br2Ca2-xNaxCuO2Br2

A comprehensive magnetic and superconducting phase diagram determined by muon spin rotation/relaxation (μSR)(μSR) is presented for Ca2-xNaxCuO2Br2Ca2-xNaxCuO2Br2 which has apical bromine atoms. Evidence for antiferromagnetic (AF) order in lightly doped samples and that for quasi-static spin glass (SG)-like state in moderately doped ones are obtained by ZF-μμSR at low temperatures. While the phase diagram is qualitatively similar to that in typical 2-1-4 cuprates including Ca2-xNaxCuO2Cl2Ca2-xNaxCuO2Cl2 and La2-xSrxCuO4La2-xSrxCuO4, it exhibits a slight shift (expansion) over the x axis.