Researchers have made a groundbreaking discovery in the field of orbitronics, a promising alternative to traditional electronics. The discovery of orbital angular momentum (OAM) monopoles in chiral topological semi-metals could lead to the development of energy-efficient devices with significant practical advantages.
Revolutionizing Electronics
The future of the electronics world is potentially standing at a few crossroads. Instead of using the charge of the electron alone to inform decisions, researchers are investigating other properties that might also provide a means for processing information and potentially leading to low-energy alternatives.
For example, electrons orbiting their atomic nucleus have a property called orbital angular momentum (OAM), and some refer to this field of spintronics as orbitronics. This nascent field offers new scope for memory devices, to potentially produce large magnetization using small charge currents, making these highly energy-efficient devices.
Finding the proper materials Benay said is what will determine the future of orbitronics, but they still need a conductor that produces stable and efficient currents of OAM. This is where the recent discovery of orbital angular momentum monopoles in chiral topological semimetals enters the play with a breakthrough.
Unveiling the Elusive OAM Monopoles
OAM monopoles have been an elusive theoretical prediction in the research discipline of orbitronics that has never been experimentally realized. In organization, these monopoles are identified with a sort of OAM texture, one where the hole indicates outwards from a focal point much like how we envision the spikes of a frightened hedgehog.
A team of researchers, led by scientists from the Paul Scherrer Institute (PSI) in Switzerland and the Max Planck Institutes for Microstructure Physics (Halle) and Chemical Physics of Solids (Dresden), has now made a huge step forward: The researchers have succeeded in combining state-of-the-art simulations with particularly novel experiments at one of PSI’s top-flight instruments — the Swiss Light Source SLS.
Our study, now published in the high-ranking journal Nature Physics, confirms that chiral topological semi-metals, a new class of materials discovered at PSI in 2019 [4], may well be best suited to realize such flows of OAMs. Due to the helical atomic structure of these materials, they are already prefabricated by nature with an OAM texture that is spontaneously created and thus there is no need to induce them externally.
But, the road to this discovery has been tumultuous. This allowed the researchers to peel off layer by layer, peeling away at every assumption that ventured out of line using both rough theory and infamously complex data from Circular Dichroism in Angle-Resolved Photoemission Spectroscopy (CD-ARPES) experiments. Which helped to become a link between theory and experiment, thus finally revealing the existence of OAM monopoles.
Conclusion
The discovery of orbital angular momentum monopoles in chiral topological semi-metals is a milestone in the field of orbitronics. The inherent OAM textures of these materials provide a promising solution for stable and effective current generation of OAM, toward realizing energy-saving electronic devices. This breakthrough now means researchers can explore OAM Textures in other materials and tailor the application to suitably match a new age of orbitronics, where before this seemed almost far-fetched.
