Self-biased magnetoelectric gyrators in composite of samarium substituted nickel zinc ferrites and piezoelectric ceramics

Magnetoelectric (ME) gyrators consisting of system of Sm-doped NiZn ferrites (Ni1-xZnxSm0.02Fe1.98O4, 0.2≤x≤0.5) and piezoelectric ceramics [Pb(Zr, Ti)O3] with coil wound around have been developed. Distinct hysteresis behaviors were observed in off-resonance ME couplings and power conversion efficiency (PE) characterizations, resulting in a non-zero ME response and anticipating a higher remanent PE at zero bias. Consequently, light samarium doping facilitates the enhancement of PE, which reaches its maximum of 81.5% under optimum bias and self-biasing value of 58.5% under zero bias in the composite of Ni0.8Zn0.2Sm0.02Fe1.98O4/PZT trilayer respectively, exhibiting approximately 2.2 times higher than the counterpart without any samarium doping. These findings provide great possibilities of ME gyrators for miniaturized devices deployed in power electronics, converters and wireless energy harvesters without a sacrifice in magneto-mechanical efficiency.