Structure and magneto-electric properties of hydrothermally prepared nanocrystalline Ga_xFe_2−xO₃ (x = 0.7, 1 & 1.3)

In this work, we report the effect of gallium content on the structure and electric, magnetic, and magnetoelectric properties of hydrothermally synthesized Ga_xFe_2−xO₃ (x = 0.7, 1 & 1.3) nanocrystalline samples. The crystal structure of samples is a single-phase trigonal structure with space group \(R\mathop 3\limits^{ - } c\) $R\stackrel{-}{3}c$ (167). The Rietveld refinement analysis confirmed the non-perovskite structure with random occupancy of Ga/Fe ions in the hexagonal lattice and shows a decrease in lattice parameters and volume with increasing Ga content. The temperature-dependent magnetizations reveal the ferrimagnetic nature of the samples at room temperature (RT), and the canted spin state decreased with Ga content. Ferroelectric polarization confirms the existence of ferroelectricity in our samples. The leakage current density, frequency-dependent dielectric constant, and polarization increase with increasing Ga concentration. Magnetoelectric studies show a linear ME coupling response for Ga_xFe_2−xO₃ samples, and the ME coupling coefficient at RT is high for GFO (α_ME = 27ps/m) with x = 1 composition.