Optimization of magnetoelectricity in piezoelectric–magnetostrictive bilayers

Abstract

Magnetoelectric coupling is of interest for a variety of applications, but is weak in monolithic materials. Strain-coupled bilayers or multilayers of piezoelectric and magnetostrictive material are an attractive way of obtaining enhanced effective magnetoelectricity. This paper studies the optimization of magnetoelectricity with respect to the crystallographic orientations and the relative thickness of the two materials. We show that the effective transverse (α E,31) and longitudinal (α E,33) coupling constants can be enhanced many-fold at the optimal orientation compared to those at normal orientation. For example, we show that the constants are 17 and 7 times larger for the optimal orientation of a lithium niobate/Terfenol-D bilayer of equal thickness compared to the normal orientation. The coupling also increases as the piezoelectric phase gets thinner.

Direct and converse magnetoelectric effects in Metglas/LiNbO3/Metglas trilayers

“…Following the procedure described in Ref. 40 and using the Metglas and PMN-PT material parameters obtained from the suppliers and from independent sources, 6,45-49 we calculated the maximal values of a E31 and a E32 for our specific samples. The obtained values were a E31 ¼ 23.2 V/(cm Oe) and a E32 ¼ À7.2 V/ (cm Oe).…”

“…Using the data for the Z-cut crystal 43 we applied a standard method 40,43,44 for the determination of the piezoelectric and other properties in the rotated (i.e., cut) crystal. The obtained physical quantities were put into the model presented in Ref.…”

“…The obtained physical quantities were put into the model presented in Ref. 40 to calculate the magnetoelectric response of the trilayers. Figure 4(a) shows the results of the calculations of the a E31 and a E32 coefficients as a function of the crystal cut angle.…”

“…[40][41][42] Calculations of the ME response for a Terfenol/LNO/ Terfenol structure were performed in Ref. 40.…”

Magnetoelectric Coupling and Overall Properties of a Class of Multiferroic Composites

“…The availability of explicit formulae for the S-tensor of a flat lamina and long circular cylinder has also greatly facilitated the study of piezoelectric multilayered structures and fibrous systems. For details one may refer to Kuo et al (2010), Bichurin et al (2003), Wang et al (2012), Liu and Kuo (2012), Kuo and Bhattacharya (2013), Chen et al (2014), andLiu et al (2014), among others.…”