WITHDRAWN: Impact of Hg doping on structural, electronic, magnetic, and thermal properties of Nd0.80Sr0.20−Hg CoO3 (0.0 ≤ x ≤ 0.15)

Nd 1− x Sr x CoO 3 (NSCO) exhibits interesting features in its phase diagram with rich magnetic phases. These features are attributed to the complex interplay between the lattice, orbital, spin, and charge degrees of freedom, as well as the additional ion spin state variance in cobaltites. In this article, we investigated the Hg-doping effects on the structural, electronic, magnetic, and thermal properties of polycrystalline Nd 0.80 Sr 0.20− x Hg x CoO 3 (0 ≤ x ≤ 0.15) series. Magnetization measurements showed that the paramagnetic (PM) to ferromagnetic (FM) transition temperature, T c , decreased as doping content increased. An Hg doping as small as 5% sufficed to destroy the long-range order. Transport measurements indicated that all samples showed the semiconducting characteristics below 300 K. The Hg doping strongly increased the magnitude of resistivity. It was confirmed that the long-range FM order in the Nd 0.80 Sr 0.20 CoO 3 parent compound formed by the coalescence of FM clusters embedded in the antiferromagnetic matrix and was strongly susceptible to disorders. The Hg doping at the Sr site strengthened the localization of itinerant carriers, weakened the double exchange interaction between Co ions, and destroyed the percolation of FM clusters. Thermopower measurements demonstrated peaks at T c , which may be attributed to the enhancement in spin polarization caused by the magnetic transition. The low temperature enhancement can be attributed to the magnon drag effect. The higher value of thermopower indicates that the series can be a promising candidate for technological applications.