Electron spins are fundamental properties of electrons that determine their magnetic behavior. In materials such as nickel oxide, the electron spins interact with the crystal lattice, giving rise to a variety of magnetic phenomena. Understanding how these interactions occur is crucial for designing new materials for magnetic data storage and other applications.
Now, a team of researchers led by the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) has made a breakthrough in understanding how electron spins interact with the crystal lattice in nickel oxide. Their findings, published in the journal Nature Communications, provide a foundation for understanding and designing new materials for magnetic data storage.
"Our study reveals the microscopic details of how electron spins interact with the lattice in nickel oxide," said lead author Yimei Zhu, a postdoctoral researcher in Berkeley Lab's Materials Sciences Division. "This understanding is essential for the rational design of new materials with desired magnetic properties."
The researchers used a combination of experimental techniques, including neutron scattering and x-ray absorption spectroscopy, to study the magnetic excitations in nickel oxide. They found that the electron spins interact with the lattice in two different ways: through the exchange interaction and the spin-orbit interaction.
The exchange interaction is a magnetic interaction between two electrons that results from the Pauli exclusion principle. The spin-orbit interaction is a relativistic effect that arises from the interaction between the electron's spin and its motion.
The researchers found that the exchange interaction is the dominant interaction in nickel oxide. However, the spin-orbit interaction also plays a significant role in determining the magnetic properties of the material.
"Our study provides a comprehensive understanding of how electron spins interact with the lattice in nickel oxide," said senior author Junjie Zhang, a staff scientist in Berkeley Lab's Materials Sciences Division. "This understanding will enable us to design new materials with tailored magnetic properties for a wide range of applications, such as magnetic data storage, spintronics, and quantum computing."
In addition to Zhu and Zhang, other researchers involved in the study include: Wenbin Wang, Xiangli Peng, and Xiao Zhang of Berkeley Lab; and Robert J. Cava of Princeton University.
This research was supported by the DOE Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract No. DE-AC02-05CH11231. Access to the Advanced Light Source beamline 12.3.2 was provided by the DOE Office of Science, Office of Basic Energy Sciences. Neutrons scattering experiments were performed at the Spallation Neutron Source (SNS), a DOE Office of Science user facility operated by Oak Ridge National Laboratory.
