  In this investigation, undoped BiFeO$_3$, Gd doped
Bi$_{0.9}$Gd$_{0.1}$FeO$_3$, and Gd-Ti co-doped
Bi$_{0.9}$Gd$_{0.1}$Fe$_{1-x}$Ti$_x$O$_3$ (x = 0.10, 0.20) materials were
synthesized to report their multiferroic properties. The structural analysis
and phase identification of these multiferroic ceramics were performed using
Rietveld refinement. The Rietveld analysis has confirmed the high phase purity
of the 10% Gd-Ti co-doped Bi$_{0.9}$Gd$_{0.1}$Fe$_{0.9}$Ti$_{0.1}$O$_3$ sample
compared to that of other compositions under investigation. The major phase of
this particular composition is of rhombohedral \textit{R3c} type structure (wt%
$>99\%$) with negligible amount of impurity phases. In terms of
characterization, we address magnetic properties of this co-doped ceramic
system by applying substantially higher magnetic fields than that applied in
previously reported investigations. The dependence of temperature and maximum
applied magnetic fields on their magnetization behavior have also been
investigated. Additionally, the leakage current density has been measured to
explore its effect on the ferroelectric properties of this multiferroic system.
The outcome of this investigation suggests that the substitution of 10% Gd and
Ti in place of Bi and Fe, respectively, in BiFeO$_3$ significantly enhances its
multiferroic properties. The improved properties of this specific composition
is associated with homogeneous reduced grain size, significant suppression of
impurity phases and reduction in leakage current density which is further
asserted by polarization vs. electric field hysteresis loop measurements.
