We report on the magnetic properties of the manganite ${\mathrm{Bi}}_{1-x}{\mathrm{Ca}}_x\mathrm{Mn}{\mathrm{O}}_3$ $(x=0.33)$ at low temperature. The analysis of the field expansion of the ac susceptibility and the observation of aging properties make clear that a spin-glass phase appears below $T=39\mathrm{K}$ in the presence of magnetic order. Neutron scattering shows both magnetic Bragg scattering and magnetic diffusion at small angles and confirms this coexistence. In contrast to ${\mathrm{Pr}}_{1-x}{\mathrm{Ca}}_x\mathrm{Mn}{\mathrm{O}}_3$ $(x=0.3–0.33)$, which exhibits a mesoscopic phase separation responsible for a field driven percolation, the glassy and short range ferromagnetic order observed here does not cause a colossal magnetoresistance.

• Received 1 February 2008

DOI:https://doi.org/10.1103/PhysRevB.77.134445