In a groundbreaking development, researchers at the University of Nebraska–Lincoln have achieved a significant milestone in antiferromagnetic spintronics, potentially revolutionizing the future of nanotechnology. This advancement addresses the longstanding challenge of high power consumption in electronic devices. By introducing boron into magnetoelectric oxides - a process known as B-doping - the team has successfully managed to control magnetic fields at the high temperatures typical of electronic devices. This achievement is hailed as a major breakthrough in the field, according to Christian Binek, a leading physics professor at the university.
Spintronics has been at the forefront of next-generation nano-electronic device development for the past three decades. However, a persistent challenge has been finding a quantum material whose magnetic states can be electronically manipulated, especially at temperatures exceeding room temperature. The Nebraska researchers' work with boron-enhanced chromium oxide could lead to digital memory and processors that are not only more energy-efficient but also faster than existing technologies. Chromium oxide is characterized by its antiferromagnetism, where alternating columns of atoms have opposing magnetic poles that effectively cancel each other out, resulting in a negligible magnetic field.
Historically, controlling the antiferromagnetic order in chromium oxide using voltage was limited due to its ineffectiveness at high temperatures and the necessity of an applied magnetic field to disrupt symmetry. Abdelghani Laraoui, an assistant professor specializing in mechanical and materials engineering, has developed a method to study and validate the boron-doping technique using nitrogen vacancy scanning probe microscopy. This innovative approach allows for direct imaging of boundary magnetization and the observation of B-doping effects, as demonstrated in a 2023 study.
Laraoui’s nitrogen vacancy imaging platform provides empirical evidence for phenomena that were previously only theoretical, as noted by Binek, who also serves as the scientific director of the Emergent Quantum Materials and Technologies collaboration (EQUATE). This research initiative, a major priority at Nebraska, was launched in 2021 with a substantial grant from the National Science Foundation. Laraoui leads the EQUATE group, which focuses on advancing quantum technologies.
The research team, in addition to Binek and Laraoui, includes Adam Erickson, a doctoral candidate in mechanical and materials engineering; Syed Qamar Abbas Shah, a doctoral candidate in physics and astronomy; Ather Mahmood, a facility specialist at the Nebraska Center for Materials and Nanoscience; Pratyush Buragohain, a Nebraska physics and astronomy doctorate now employed at Intel Corporation; Ilja Fescenko, a research scientist at the University of Latvia; and Alexei Gruverman, a distinguished physics professor. Their findings are comprehensively detailed in the journal Advanced Functional Materials.