Nonlinear magnetodielectric effect of disordered perovskite HoCr0.5Fe0.5O3: Role of magnetic rare-earth ions

We investigated the magnetic and dielectric properties of perovskite HoCr0.5Fe0.5O3. The coexistence of various magnetic interactions resulting from disordered transition-metal ions leads to an intricate temperature dependence of the magnetic properties. From the examination of the temperature dependence of magnetic susceptibility and heat capacity, an antiferromagnetic order of Cr3(+)/Fe(3+)moments arises below T-N = 304 K and a spin reorientation transition occurs at T-SR = 170 K. In addition, an antiferromagnetic order of Ho3- spins emerges at T-Ho = 18 K. Based on the sufficiently low dielectric loss below 150 K, excluding the influence of extrinsic effects, a highly nonlinear variation in the isothermal dielectric constant, with a similar hysteretic behavior of the magnetic-field derivative of magnetization, is observed. In comparison to the lack of a noticeable magnetodielectric effect in YCr0.5Fe0.5O3, the strong correlation between magnetic and dielectric order parameters in HoCr0.5Fe0.5O3 suggests the important role of magnetic rare-earth Ho3+ ions. Our results accompanied by intricate magnetic correlations in the disordered HoCr0.5Fe0.5O3 are expected to trigger fundamental and applied research on magnetic materials through the scope of specific magnetic characteristics in disordered perovskites. (C) 2019 Elsevier B.V. All rights reserved.