Ultra-High Sensitive Magnetoelectric Nanocomposites Current Sensors

摘要

We investigated the synthesis and characterization of magnetoelectric (ME) 3-2 nanocomposite thick films using aerosol-deposition (AD). Piezoelectric and magnetostrictive materials were simultaneously deposited on a platinized silicon substrate using AD method and a 13 micron thick nanocomposite film was realized. Upon annealing, magnetostrictive phase was found to form a layered structure inside the piezoelectric matrix. Detailed microstructural analysis revealed the connectivity of individual phases. This nanocomposite thick film was found to exhibit the ME coefficient of the order of 150 mVcm-1Oe-1 which is significantly higher in comparison to other results reported in literature on ME thin/thick films. For bulk composites, we developed a 2-1-2 magnetoelectric laminate composite having configuration Metglas / PZNT / Metglas with ferrite pillars embedded in the PZNT phase. The piezoelectric layer with composition 0.2Pb(Zn1/3Nb2/ 3)O3-0.8Pb(Zr0.5Ti0.5)O3 (PZNT) consisted of co-fired (Ni0.6Cu0.2Zn0.2)Fe2O3 (NCZF) pillars. This 2-1-2 composite was found to exhibit the ME coefficient of the order of 352 mV/cm.Oe. Interestingly, the performance of 2-1-2 composite is 15% higher than that of conventional 2-2 laminate composite. Using these composites we developed a broadband ME sensor exhibiting flat response over a wide range of frequency and magnetic DC bias. The sensitivity of bending mode sensor was demonstrated to be 5 nT at room temperature.