Correlation between Local Distortion and Multiferroic Interaction in the Nanostructured Bi5Ti3FeO15 System

• Grant number: 25/02737-8
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2025
• End date: July 31, 2029
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Fabio Luis Zabotto
• Grantee: Vitor Melo Frata Barbosa
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 24/20319-6 - Mulferroism and Magnetoelectric Coupling in Nanostructured Aurivillius Phase Materials, AP.R

Abstract

Materials that exhibit the magnetoelectric effect have attracted increasing scientific and technological interest due to the possibility of integrating highly relevant properties, such as ferroelectricity and ferromagnetism, in addition to allowing the manipulation of these orders by external fields simultaneously. However, the development of these materials is a challenge, given the intrinsic incompatibility between the magnetic ordering and the structural distortions stabilized by the Pseudo-Jahn-Teller effect, which are fundamental for ferroelectricity in many systems. In this context, epitaxial nanostructures based on the four-layer Aurivillius system, Bi5Ti3FeO15 (BFT4), stand out as promising candidates, presenting multiferroicity and magnetoelectric coupling at room temperature. Consequently, in recent years there has been an increase in interest in manipulating these structures at the atomic level in order to improve their physical properties, motivating several theoretical and experimental studies on the correlation between magnetic percolation, local structural distortions and magnetoelectric coupling. Thus, this project aims to deepen the understanding of the multiferroic nature of Bi5Ti3FeO15 and the mechanisms that govern the magnetoelectric effect. To this end, we will investigate how epitaxial strain influences these properties by modifying local distortions and the occupation of magnetic ions in the lattice. To establish this correlation, epitaxial thin films will be grown on NdGaO3, LaAlO3 and DyScO3 substrates, allowing us to analyze how the induced structural changes impact the evolution of the multiferroic and magnetoelectric responses. (AU)