In recent years, a variety of bulk magnetoelectric (ME) composite materials with different phase connectivity, i.e., (0-3), (1-3), (2-2), (2-1) etc, have been paid extensive attention, and tremendous progress has been achieved. But further development of ME composites seems to run into a dead ends.
Recently, Prof. Shuxiang Dong’s group made a breakthrough in further intensifying ME coupling by designing a (1-1) ME composite consisting of a -oriented Pb(Mg,Nb)O3-PbTiO3 (PMN-PT) single crystal fiber laminated with laser-treated amorphous FeBSi alloy (Metglas). It is found the laser treatment of Metglas alloy can increase the mechanical quality factor Qm significantly due to the nano-crystallization of magnetic phase, which in turn results in lower resonance loss of Metglas alloy and therefore enhances ME coupling at electromechanical resonance. Finally, an extremely high ME coupling coefficient of ~7000 V cm-1Oe-1 was achieved, which is 7 times higher than the best result published formerly in ME composites. Correspondingly, a super-high AC magnetic field sensitivity was found to be 1.35*10-13 Tesla at resonance and at room temperature, which can be viewed as a potential alternative to extremely sensitive magnetic field sensors.
This work was just published as a communication in the top journal Advanced Materials.(IF=18.9) http://dx.doi.org/10.1002/adma.201606022
The schematic view for the structure, prototype snapshot and ME coupling process of the proposed (1-1) laminated ME composite
Prof. Shuxiang Dong’s group has been devoting to the development of piezoelectric, magnetoelectric composites, and magnetoelectric sensors. Prof. Shuxiang Dong proposed an equivalent circuit mode for magnetic-elastic-electric coupling, found the magnetoelectric gyration effect and first reported the ME composites consisting of piezoelectric fibers and iron-based amorphous alloy. The multi-push-pull mode and L-T mode defined by Prof. Shuxiang Dong received wide recognition and adoption all over the world.
The co-first authors for this work are Zhaoqiang Chu and Huaduo Shi, Ph.D. students in the college of Engineering who started their studies in year 2015 and 2011, respectively. The National Natural Science Foundation of China and Beijing Scientific Association have funded this work.