Challenges and opportunities in orbitronics

Abstract

The ability to control the spin degrees of freedom of electrons has enabled the development of spintronic devices that use spin, rather than just electric charge, to store and process information. The concepts of spintronics are now applied in technologies such as magnetic sensors and non-volatile memory devices. In addition to spin, electrons can carry orbital angular momentum. However, research into the use of orbital angular momentum is still in its early stages. Recent discoveries of phenomena mediated by orbital angular momentum have led to a new branch of physics called orbitronics. Here we explore how orbitronics may represent the next phase in the evolution of spintronics by reviewing the current theoretical understanding, challenges and experimental results related to orbital effects. We also outline key open questions and discusses potential applications, with a focus on non-volatile memory technologies.