Studies of exchange spring and exchange bias couplings using transport measurement, magnetization and FORCs analysis in FM1/IrMn/FM2 trilayers

• Grant number: 15/09053-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2015
• End date: July 31, 2016
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Luiz Carlos Camargo Miranda Nagamine
• Grantee: Guilherme Barbosa Barros
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

This work focuses on the studies of exchange spring and exchange bias in trilayers, in which these phenomena are not fully understood. These interactions have wide application in recently developed technological devices, such as magnetic memory and recording media. For better understanding of these phenomena, FM1/AFM/FM2 trilayers are prepared by sputtering and after thermally treated with applied magnetic field. Magnetic characterizations will be carried out using an alternating force magnetometer, a vibrating sample magnetometer and Extraordinary Hall Effect measurements. For some samples, First Order Reversal Curves (FORCs) will be done for some selected hysterical curves. Always as possible, we will make magnetization curve fitting using a domain wall model, with the purpose of extracting parameters related with the magnetic anisotropy and interlayer interactions. Therefore, the comparison of these parameters with those obtained with the analysis of FORCs diagrams will be possible, with the purpose of a better understanding of the spiral domain formation inside the antiferromagnetic material and the existence of such domains in systems with perpendicular anisotropy.