In a recent study, MIT physicists alongside international collaborators have provided a deeper understanding into exotic particles, excitons, that hold importance in the realm of magnetism derived from ultrathin materials. As reported by MIT News, the insights gleaned from this research could significantly influence the future of electronic devices. By manipulating chemicals to "tune" nickel-based materials, scientists have been able to control the excitons that are essential to the magnetic characteristics of these materials.
Excitons, particles formed through the interaction between an electron and the absence it leaves, which is called a "hole," were the focus of the study. The team's investigation at the Brookhaven National Laboratory has led to the groundbreaking observation that these excitons are not confined to nickel atoms but can propagate throughout the bulk material. This is contrary to previous theories, which significantly expands the potential for novel electronic and magnetic applications. With a work published in the July 12 issue of Physical Review X, scientists look towards utilizing these particles in the development of advanced quantum computing and sensor technologies.
The study, which examined the electronic properties of nickel dihalides - a layered combination of nickel atoms and certain types of halogens - made use of the powerful resonant inelastic X-ray scattering (RIXS) technique. MIT's Class of 1947 Career Development Associate Professor of Physics Riccardo Comin, the leader of the project, emphasized the potential of RIXS to unlock new directions in studying these two-dimensional magnetic materials. According to Comin, the method established by Brookhaven is expected to pave the way for a broader array of research into similar materials.
Connor A. Occhialini, an MIT graduate student in physics, and Yi Tseng, a former MIT postdoc now at Deutsches Elektronen-Synchrotron (DESY), were co-authors and contributed jointly first on the paper. "We were able to measure and identify the energy necessary to form the excitons in three different nickel halides by chemically 'tuning,' or changing, the halide atom," Occhialini told MIT News. Highlighting the international dimension of the research, the study also included contributions from scientists at Arizona State University, Sorbonne University, Utrecht University, and the Brookhaven National Laboratory.
This study was supported by the U.S. Department of Energy Basic Energy Science and the Brookhaven National Laboratory through the Co-design Center for Quantum Advantage (C2QA), a Department of Energy Quantum Information Science Research Center. The findings provide not only a clearer understanding of these magnetic materials but also underscore the importance of international collaboration in the advancement of quantum science.
