Crystal structural, magnetic, and dielectric properties of Cobalt-doped breathing pyrochlore LiInCr_4-xCo_xO₈

Here, the structural, magnetic, and dielectric features of breathing pyrochlore LiInCr4-xCoxO8 were investigated. The XRD analysis showed changes in Cr-Cr length and distorted CrO6 octahedral as Co ion doping level rises. The x-ray photoemission spectroscopy measurements showed that there are both Co2+ and Co3+ ions in the LiInCr4-xCoxO8 compounds. The difference between temperature-dependent magnetization curves during field cooling and zero-field cooling suggested that there is a spin-glass state, which was verified by the heat capacity measurement. Doping affects the bond length, which affects the magnetic properties and electronic properties. The dielectric characteristics were systematically studied, and the temperature dependence of the dielectric loss and dielectric constant was examined in the temperature range of 323-573 K at various frequencies. The dielectric behavior strongly changes with the change in temperature and/or frequency. The activation energies of grain boundary resistance of doped samples show a decreasing trend with increasing doping.