Ferromagnetic correlations in the highly frustrated, spin-glass-like, pyrochlore oxide Y2Mn2O7, a neutron scattering study

Previous studies have shown that Y2Mn2O7 is spin-glass-like with no long range order to 2 K in spite of bulk magnetic susceptibility data which suggest ferromagnetic order below 20 K. This compound has been studied by small angle neutron scattering (SANS) over the Q-range 0.02 Å−1 to 0.15 Å and the temperature range 8 K to 100 K. Direct evidence for the presence of finite-size ferromagnetic clusters is seen in the form of strong scattering at …