  In this report we present results of magnetization measurements and
investigation of aging and memory effect in bismuth ferrite multiferroic
micro-cubes obtained by means of simple microwave synthesis procedure. It is
found that difference between FC and ZFC magnetizations appears at the
temperature of freezing of ferromagnetic domain walls. The decay of the
magnetic moment vs. time described by power-law relation and the absence of
memory effect indicate domain growth mechanism rather than the spin-glass
phase.
