Coexistence of spin glass type freezing and cooperative paramagnetic state in Sr3MnTiOT7.

We report on the unusual magnetic properties in a double layer Ruddlesden-Popper phase tetragonal Sr3MnTi07 by the measurements of dc magnetization, heat capacity, and neutron diffraction data. Despite of a high Curie- Weiss temperature of 427 K, no long-range magnetic order was observed down to 3.5 K. below which the magnetic susceptibility χ(T) and thermodynamic results suggest the presence of a glassy phase in magnetism. By the analysis of the nonlinear component of dc susceptibility and the corresponding scaling behavior, it is shown that the nature of the magnetic state below 3.5 K is not a true conventional spin glass type. Moreover, the low temperature magnetic susceptibility and specific heat behavior were found to be strikingly similar to that of lightly doped spin liquid systems. On the basis of the above results, we predict the coexistence of correlated (spin liquid) and uncorrelated spin (spin glass) states in Sr3MnTiO7. [ABSTRACT FROM AUTHOR]