MemberSeptember 10, 2021 at 10:44 am
Using a new technique called HARPES, a team of scientists look to uncover the origin of the ferromagnetism in dilute magnetic semiconductors.
Spintronic technology, in which data is processed on the basis of electron “spin” rather than charge, promises to revolutionize the computing industry with smaller, faster and more energy efficient data storage and processing. Materials drawing a lot of attention for spintronic applications are dilute magnetic semiconductors – normal semiconductors to which a small amount of magnetic atoms is added to make them ferromagnetic. Understanding the source of ferromagnetism in dilute magnetic semiconductors has been a major road-block impeding their further development and use in spintronics. Now a significant step to removing this road-block has been taken.
A multi-institutional collaboration of researchers led by scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), using a new technique called HARPES, for Hard x-ray Angle-Resolved PhotoEmission Spectroscopy, has investigated the bulk electronic structure of the prototypical dilute magnetic semiconductor gallium manganese arsenide. Their findings show that the material’s ferromagnetism arises from both of the two different mechanisms that have been proposed to explain it.
“This study represents the first application of HARPES to a forefront problem in materials science, uncovering the origin of the ferromagnetism in the so-called dilute magnetic semiconductors,” says Charles Fadley, the physicist who led the development of HARPES. “Our results also suggest that the HARPES technique should be broadly applicable to many new classes of materials in the future.”