Structure, Magnetism and Electrical Transport of Electron Doped SrCo0.5Nb0.5O3

A-site nominal doping of disordered perovskite SrCo
0.5
Nb
0.5
O
3
with La
³⁺
, Nd
³⁺
showed a shift in transition temperature to lower temperatures. Sr
0.9
A
0.1
(CoNb)
0.5
O
3
(A=La, Nd) forms in the tetragonal structure with
$I4/m$
symmetry. An increase in unit cell dimensions for La doped sample is observed. Whereas, the Nd doped samples show a decrease in unit cell volume. Electron doping introduces 2+ oxidation state for Co ions, with the Co
³⁺
state still present in the system. Competing ferromagnetic and antiferromagnetic interactions are present in the samples, with a rise in antiferromagnetic nature of magnetism exhibited by doped samples. The samples are highly insulating, with the Sr
0.9
Nd
0.1
(CoNb)
0.5
O
3
showing highest resistivity. The high resistivity in the doped samples is consistent with the increase in antiferromagnetic interactions in those.