  We report the results of our investigation of magnetic, thermodynamic and
dielectric properties of Ca substituted half-doped orthochromite,
Dy0.6Ca0.4Fe0.5Cr0.5O3. Magnetic susceptibility and heat capacity data bring
out that this compound undergoes two antiferromagnetic transitions, one at ~132
and the other at ~22 K. These values are higher than those of DyFe0.5Cr0.5O3.
This finding highlights that non-magnetic hole doping in form of Ca+2 in the
place of magnetic Dy+3 tends to enhance magnetic transition temperatures in
this half-doped orthochromite. We attribute it to possible change in the
valence state of Cr/ Fe-ion ions due to hole doping. Dielectric anomalies are
also seen near the magnetic ordering temperatures indicating magnetodielectric
coupling, which is confirmed by magnetic field dependent dielectric studies.
The most notable observation is that magnetodielectric coupling strength gets
significantly enhanced as compared to DyFe0.5Cr0.5O3. The results reveal that
it is possible to tune magnetodielectric coupling by hole doping in this
system.
