Enhanced magnetic and ferroelectric properties of multiferroic CuCrO2 by Ni-doping

We prepare polycrystalline CuCrO2 and CuCr0.98Ni0.02O2 samples by solid state reaction and investigate their multiferroicity. It is revealed that the Ni-doping can not only enhance slightly magnetization but also improve ferroelectricity. It is argued that the Ni3+-doping destabilizes the antiferromagnetic order of Cr3+ ions and modulates the spin configuration, leading to the weak ferromagnetism and enhanced ferroelectric polarization. The coupling between the magnetic order and ferroelectric order is also characterized.