DC conduction mechanisms in Sr-Co-Ti and Sr-Mn-Ti hexagonal ferrites

In this work, we have investigated the Current Density (J) - Electric Field (E) characteristics of M-Type SrCoxTixFe(12-2x)O19 and SrMnxTixFe(12-2x)O19 hexagonal ferrites and discussed linear as well as non-linear conduction mechanisms which include Schottky-Richardson, Poole-Frenkel mechanism, Space Charge Limited Conduction (SCLC) mechanism, Ionic Hopping mechanism. In SrCoxTixFe(12-2x)O19 ferrites, The Schottky-Richardson conduction is observed in x=0.2 from 2.88 kV/m to 3.43 kV/m. The Poole-Frenkel mechanism is observed in compositions x=0.0, 0.2, 0.3 and 0.6 from 1.87 kV/m to 2.16 kV/m, 0.66 kV/m to 0.73 kV/m, 1.93 kV/m to 2.25 kV/m and 2.75 kV/m to 3.04 kV/m respectively. In SrMnxTixFe(12-2x)O19 ferrites, the Schottky-Richardson mechanism is observed in x=0.5, 1.0, 1.5 and 2.0 at an applied field from 25.90 kV/m to 26.93 kV/m, 20.81 kV/m to 21.33 kV/m, 19.79 kV/m to 20.08 kV/m and 20.30 kV/m to 22.77 kV/m respectively. The Poole-Frenkel mechanism is observed in x=0.5, 1.0, 1.5 and 2.0 from 14.58 kV/m to 14.93 kV/m, 9.81 kV/m to 10.20 kV/m, 18.43 kV/m to 18.70 kV/m and 17.34 kV/m to 18.41 kV/m respectively. All compositions behave as semiconductor at low applied field.