We report structural, detailed DC and linear/non-linear AC, isothermal and
thermoremanent magnetization study of the rutheno-cuprate superconducting
ferromagnet RuSr2Gd1.4Ce0.6Cu2O10-{\delta} (GdRu-1222). Structural analysis, by
employing Rietveld refinement of X-ray diffraction pattern, reveals that
GdRu-1222 crystallizes in tetragonal phase with I4/mmm space group. GdRu-1222
is a reported superconducting ferromagnet with Ru spins magnetic ordering at
around 110 K and superconductivity below 40 K in Cu-O2 planes. Detailed
linear/non-linear first and higher order harmonic of AC susceptibility studies
unveiled the complex magnetism of GdRu-1222. A frequency dependent cusp is
observed in AC susceptibility ({\chi}ac) vs. T measurements. The change in cusp
position with applied frequency followed the well known Vogel-Fulcher law,
which is a feature to describe a spin-glass (SG) system with possibility of
embedded homogeneous/non-homogeneous magnetically interacting/non-interacting
ferromagnetic clusters. Such an interpretation is also supported by
thermoremanent magnetization (TRM) study at T = 60 K. Detailed interpretation
of AC magnetization results revealed the formation of magnetic (ferromagnetic)
homogenous/non-homogenous clusters of different sizes embedded in spin-glass
(SG) matrix. The magnetization vs. applied field loops do not saturate, even at
high applied fields (50 kOe), resulting in the short-range magnetic ordering in
the system, which causes the formation of clusters that freeze at low
temperatures. Temperature variation of first- and third-order susceptibility
harmonics show good agreement with Wohlfarth's model (WM), leading to the
superparamagnetism (SPM) state. Detailed magnetization (DC and AC both) results
and their analysis helped in explaining the temperature dependent magnetism of
the GdRu-1222 system.Comment: 24 Pages Text + Figures; Comments/Suggestions
([email protected])/www.freewebs.com/vpsawana