Researchers demonstrate generation of orbital current via magnetization dynamics

While the field of spintronics tries to leverage the spin angular momentum of electrons to develop new technologies, these particles' orbital momentum has so far been rarely considered. Currently, generating an orbital current (i.e., a flow of orbital angular momentum) remains far more challenging than generating a spin current. Nonetheless, approaches to successfully leveraging the orbital angular momentum of electrons could open the possibility for the development of a new class of devices called orbitronics.

Researchers at Japan's Keio University and Germany's Johannes Gutenberg University have reported the successful generation of an orbital current from magnetization dynamics, a phenomenon called orbital pumping. Their outlines a promising approach that could allow engineers to develop new technologies leveraging the orbital angular momentum of electrons.


The team stated that its work was inspired by ongoing research in spintronics and orbitronics, the orbital analog of spintronics. The recent study draws inspiration from spin pumping, a well-established phenomenon that allows engineers to generate spin currents. The key objective of their study was to realize this phenomenon's orbital counterpart, dubbed orbital pumping.

Orbital pumping essentially entails the generation of an orbital current via the dynamics of magnetization (i.e., the density of magnetic dipole moments induced in magnetic materials when they are placed near a magnet). To conduct their experiments, the scientists used a bilayer structure made of nickel and titanium.

By applying a magnetic field to their nickel and titanium structure, the researchers were able to successfully demonstrate orbital pumping. The techniques they used thus ultimately proved effective in generating an orbital current in an experimental setting.

The promising results could pave the way for new studies aimed at generating orbital currents via magnetization. These works could eventually lead to the introduction of orbitronic devices, a class of electronics that has so far been largely overlooked.

Posted: Jul 11,2024 by Roni Peleg