Evidence of low field magnetoimpedance effect in (111) oriented $Fe3O4$ thin films

Thin film of $Fe3O4$ is grown on (100) oriented GaAs substrate using pulsed laser deposition (PLD). The films were found to be (111) oriented. They were characterized morphologically as well as magnetically. They show Verwey transition at 120 K with the coercivity of 220 Oe at room temperature. These films were found to show magnetoimpedance effect with the ac magnetoresistance (MR_ac) of the order of ∼ −6% at 10 MHz, at room temperature. The MR_ac was found to increase in low field- low frequency regime and decrease in low field high frequency regime.