Tuning of Magnetic Ordering by Y Substitution in Ca₃Co₂O₆

Abstract

We have studied the magnetic and thermal properties of Y substituted Ca₃Co₂O₆. Ca₃Co₂O₆ exhibits the ferrimagnetic ground state due to ferromagnetic intrachain coupling and antiferromagnetic interchain coupling. As Y substitution increases, which results in variation of the interaction strength of both interchain and intrachain coupling, gradual but unique changes of ground state from ferrimagnetic to nonmagnetic state have been observed in dc susceptibility, isothermal magnetization, heat capacity, and ac susceptibility. Y substitution induces site percolation on Co–O one-dimensional (1D) chain as well as Co two-dimensional (2D) triangular lattice, and site percolation as well as frustration explains experimental results of doped Co–O 1D chain system. The spin configuration of the Y substituted Ca₃Co₂O₆ can be understood by using crystal field splitting model.