High-frequency magnetoelectric coupling study in multiferroic composites

• Grant number: 19/24603-2
• Support Opportunities: Regular Research Grants
• Start date: July 01, 2020
• End date: January 31, 2023
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Alexandre José Gualdi
• Grantee: Alexandre José Gualdi
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Composite multiferroic materials are a combination of two or more materials with different ferroic orders. Because it is possible, in the same device, to obtain inherent properties for each phase, these materials have been extensively studied. For example, magnetoelectricity arises from the coupling between electric and magnetic fields due to the presence of piezoelectric and magnetostrictive materials, respectively. In composite multiferroic materials, this effect arises due to the mechanical coupling between the two phases: the magnetostrictive deformation of the ferromagnetic phase causes stress in the ferroelectric phase, changing its polarization state. High values for the magnetoelectric coefficient are observed when the excitation frequency of the AC magnetic field is the same as the Electromechanical Resonance Frequency (EMR) of these composites.In this sense, this research project aims to study the behavior of magnetoelectric coupling in samples of multiferroic composites with different compositions and at high frequencies. In particular, the study will focus on samples sintered with the KxN(1-x)NbO3 (KNN) ferroelectric, whose main feature is that it is a lead-free ferroelectric. For the ferromagnetic phase, nickel and cobalt ferrite will be used. This study will be done by measuring high-frequency magnetoelectricity, near EMR, and applying a DC bias magnetic field. Thus, a better understanding of the magnetoelectric effect in this frequency range is expected. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CHAVES, DAVI A. D.; ZABOTTO, FABIO L.; ORTIZ, WILSON A.; GUALDI, ALEXANDRE J.. PMN-PT/NFO magnetoelectric characterization and the advantages of the dynamic stress magnetization model. Ferroelectrics, v. 582, n. 1, p. 12-20, OCT 22 2021. (19/24603-2, 19/03110-8)