  We report on the observation of exchange bias and memory effect in double
perovskite Sr$_2$FeCoO$_6$. Antiphase boundaries between the ferromagnetic and
antiferromagnetic regions in the disordered glassy phase is assumed as
responsible for the observed effect which reflects in the cooling field
dependence and temperature evolution of exchange bias field and in training
effect. The spin glass phase itself is characterized through memory, ageing and
magnetic relaxation experiments. The spin glass transition temperature, $T_g$,
versus $H_{dc}^{2/3}$ follows the Almeida-Thouless line yielding a freezing
temperature, $T_f$ = 73 K. Time-dependent magnetic relaxation studies reveal
the magnetization dynamics of the underlying glassy phase in this double
perovskite.

Strongly Correlated Electrons;Materials Science