Thermal effects in magnetoelectric properties of NiFe₂O₄/Pb(Zr_0.52Ti_0.48)O₃/NiFe₂O₄ tri-layered composite

ABSTRACT

Layered composite electro-ceramics can be designed to exhibit the magnetoelectric (ME) effect based on stress transfer from magnetostriction of ferromagnetic layer to the ferroelectric layer. Many studies in search of giant ME coefficients in layered composites have been made but there are less studies regarding the ME effect in these ceramic materials as a function of temperature, mainly at low temperatures. With the influential increase in magnetoelectric sensing devices use in extreme, minute or precise field monitoring, a broadband temperature dependent analysis on ME effect of these sensors is much required. In this work the effect of temperature on ME effect in a NiFe₂O₄/Pb(Zr_0.52Ti_0.48)O₃/NiFe₂O₄ layered composite are studied and any major/minute change have been analyzed. Dynamic ME measurements shows a maximum linear ME coefficient (α_ME = 238 mV/cm.Oe) by applying an AC magnetic field in a frequency of 600 Hz at room. Highly reduced α_ME values are observed at low temperatures. Magnetocapacitance effect studies showed a strong magnetoelectric coupling at room temperature and, also, a dramatic reduction in the magnetoelectric coupling at 200 K and 100 K. Analyzing the phenomena mathematically shows that there is a secondary effect interaction which influences the ME effect intensity depending on temperature.

KEYWORDS:

• Magnetoelectric effect
• 2-2 ceramic composites
• magnetocapacitance

Acknowledgments

LFC would like to thank the CAPES Brazilian agency (proc. 10069/12-7) for financial support and UTSA under the INAMM/NSF program for hosting him.