Muon-spin rotation measurements have been performed on insulating samples of Y-doped ${\mathrm{Bi}}_2{\mathrm{Sr}}_2\mathrm{Ca}{\mathrm{Cu}}_2{\mathrm{O}}_x$. In ${\mathrm{Bi}}_2{\mathrm{Sr}}_2\mathrm{Y}{\mathrm{Cu}}_2{\mathrm{O}}_x$ muon-spin precession frequencies have been observed in zero applied field which are attributed to antiferromagnetic ordering, probably in the Cu${\mathrm{O}}_2$ planes. The transition is broad with an ordering temperature of about 210 K. ${\mathrm{Bi}}_2\mathrm{SrYCa}{\mathrm{Cu}}_2{\mathrm{O}}_x$ appears to be a disordered magnetic system with a spin-freezing temperature of 15 K. These results establish that there are strong magnetic correlations in the Bi 2:2:1:2 phase which are analogous to those observed previously in ${\mathrm{La}}_{2-x}{\mathrm{Sr}}_x\mathrm{Cu}{\mathrm{O}}_4$ and $\mathrm{Y}{\mathrm{Ba}}_2{\mathrm{Cu}}_3{\mathrm{O}}_x$.

• Received 18 August 1988

DOI:https://doi.org/10.1103/PhysRevB.39.847