Chiral Phonons Transfer Orbital Angular Momentum in Non-Magnetic Materials, Clearing a Path for Orbitronics

Spin is already at work in your hard drive. Spintronics - the technology that exploits the quantum spin of electrons to store and read data - has been commercially deployed for decades, driving the density of magnetic storage to levels that would have seemed implausible in earlier eras. Researchers have been looking for a similarly exploitable electron property that could extend the principle to logic operations and fast data transport. Orbital angular momentum, the quantum property associated with the path an electron traces around its nucleus, is the most promising candidate. The field built around it is called orbitronics.

The catch has been that controlling orbital angular momentum typically requires magnetic materials - transition metals like iron, cobalt, and nickel - that are heavy, expensive, and increasingly classified as critical or strategic materials subject to supply chain risk. A study published in Nature Physics on January 21, 2026, reports a way around that constraint, using a phenomenon found in certain non-magnetic materials called chiral phonons.

What makes a phonon chiral

Phonons are the collective vibrations that travel through solid materials - the quantum analog of sound waves, rippling through the atomic lattice of a crystal. In most materials, atoms vibrate symmetrically: push them one way, they push back. In chiral materials, the atomic lattice is twisted into a helical pattern, like the thread of a screw. That built-in twist forces the atoms to vibrate not straight back and forth but in a corkscrewing rotation - either left-handed or right-handed, depending on the material's handedness.

Quartz is a classic example. Its silicon and oxygen atoms arrange in a helix, and the resulting lattice vibrations have a handedness that cannot be superimposed on their mirror image - the same symmetry property that distinguishes your left hand from your right.

The research team, led by North Carolina State University with collaborators including the University of Utah, showed for the first time that these chiral phonons can directly transfer orbital angular momentum to electrons in the same non-magnetic material. The result is a current of electrons carrying orbital angular momentum - an orbital current - generated without any magnetic material, applied voltage, or external electric current.

Why this matters for computing

Valy Vardeny, a distinguished professor at the University of Utah's Department of Physics and Astronomy and a co-author of the study, puts the significance plainly: "We don't need a magnet. We don't need a battery. We don't need to use voltage. We just need a material with chiral phonons."

That simplification removes several of the practical barriers to building orbitronic devices. Current methods for generating orbital angular momentum typically require specific transition metals - many of which appear on critical materials lists in the US, EU, and other jurisdictions due to limited supply and geopolitical concentration of reserves. A method that works in cheap, abundant materials like quartz would make orbitronic devices far more practical to manufacture and scale.

Dali Sun, a physicist at NC State and co-author of the study, explains the conventional limitation: "The generation of orbital currents traditionally necessitates the injection of charge current into specific transition metals, and many of these elements are now classified as critical materials. There are other ways to generate orbital angular momentum, but this method allows for the use of cheaper, more abundant materials."

The mechanism in detail

The innovation is using the natural geometry of the atomic lattice rather than an external field to control electron orbital states. When chiral phonons propagate through the crystal, their rotational motion couples to the orbital angular momentum of the electrons around them. This coupling - previously theorized but not experimentally confirmed in a non-magnetic system - transfers the phonon's chirality to the electron's orbital motion.

The experiment demonstrated this transfer directly, measuring orbital currents in the material and confirming their dependence on the phonon chirality. The finding closes a gap between theoretical predictions and experimental reality that had held back the field.

Where the research stands

The demonstration is at the materials physics level - a proof of concept showing the mechanism works in a controlled experimental setting. Converting that proof into a functional orbitronic device requires engineering the effect into structures that can be fabricated, integrated into circuits, and operated reliably at relevant speeds and temperatures.

Orbitronics as a field is considerably less mature than spintronics was when the first commercial spin-valve read heads appeared in hard drives. The timeline from this kind of fundamental physics result to devices in products is typically measured in decades rather than years. The significance of the work is in establishing that a key assumed constraint - the need for magnetic materials - can be bypassed using phonon physics, which opens a substantially wider range of materials and device geometries for future exploration.