Effect of La3+ ions substituted M-type barium hexa-ferrite on magnetic, optical, and dielectric properties

M-type barium hexa-ferrites having general formula Ba1−xLaxFe12O19 (x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5) have been prepared through conventional ceramic route. The effect of La3+ ions on structural, surface morphological, optical, magnetic, and frequency-dependent dielectric properties has been investigated through X-ray diffractometer, Fourier transmission infrared spectroscopy, scanning electron microscope, UV–visible spectrophotometer, vibrating sample magnetometer, and inductor capacitor and resistance meter, respectively. XRD confirms the hexagonal structure of La3+-substituted Ba hexa-ferrites. FTIR confirmed that bands in the range 500–600 cm−1 might be due to the stretching vibration of oxygen and metal (Fe–O) ions which confirm the formation of hexa-ferrite. The band-gap energy decreases with increasing concentration of La3+ ions. The coercivity increases with the La3+ substitutions due to high magnetocrystalline anisotropy. It is observed that the dielectric constant and conductivity increase, while tangent loss decreases, as the frequency increases.