Broad-band microwave absorption and magnetic properties of M-type Ba(1-2x)LaxNaxFe10Co0.5TiMn0.5O19 hexagonal ferrite in 18.0-26.5 GHz frequency range

La-Na co-substituted M-type Co-Ti-Mn barium hexaferrites Ba(1-2x)LaxNaxFe10Co0.5TiMn0.5O19 (0.00 <= x <= 0.25) were synthesized by conventional solid-state method. The influence of La-Na doping on the magnetic properties was investigated through VSM (vibrating sample magnetometer). The room temperature hysteresis loops show that the saturation magnetization decreases from 55.667 emu/g for x = 0.00 to 44.768 emu/g for x = 0.25 sample. To determine the complex permittivity (epsilon(r) = epsilon' - i epsilon '') and permeability (mu(r) = mu' - i mu '') in 18.0-26.5 GHz frequency range, a vector network analyzer was employed. Reflection loss (RL) values were simulated from the values of epsilon(r) and mu(r) acquired using transmission line theory. The minimum RL obtained for the sample x = 0.10 is -45.94 dB (99.997% signal absorption) with an absorption bandwidth of 8.33 GHz for 1.3 mm sample thickness. Thus, the synthesized hexaferrites can be utilised in electromagnetic shielding and radar stealth technology applications.