High-throughput analysis of magnetic phase transition by combining table-top sputtering, photoemission electron microscopy, and Landau theory

Abstract

Owing to recent advances in material informatics, there has been increasing interest in combinatorial experimental systems for material development. We demonstrate a novel high-throughput experiment combining compact materials synthesis, synchrotron radiation measurements, and statistical data analysis. This technique focuses on not only drawing phase diagrams but also analysing phase transitions for exploring the functions of magnetic materials. In this study, a composition-gradient Fe–Co–Cr ternary thin film was prepared using a table-top sputtering system and a 3D printer. The chemical components and magnetic contrast were measured using photoemission electron microscopy through the acquisition of 1 million spectral datasets within 10 min. The ternary magnetic-phase diagram of Fe–Co–Cr obtained by statistical analysis of the magnetic circular dichroism (MCD) contrast images agreed with ferromagnetic/paramagnetic transition. The MCD histogram was fitted based on Landau theory, and the estimated critical exponent β (0.36 ± 0.028) agreed well with previous theoretical and experimental studies. This study demonstrates universal physical parameter analysis that characterises magnetic properties by a high-throughput approach combined with a simple experimental apparatus.

Keywords

• high-throughput experiment
• photoemission electron microscopy
• phase diagrams
• x-ray absorption spectra
• statistical data analysis
• magnetic circular dichroism