Scientists just found a way to control electrons without magnets

 As computing demands continue to surge, scientists are exploring the quantum world for smarter ways to process massive amounts of data. One promising direction is a field called orbitronics, which focuses on using the motion of electrons around an atom's nucleus, known as orbital angular momentum, to carry and store information more efficiently. Traditionally, controlling this motion has required magnetic materials such as iron, which are heavy, costly, and difficult to scale for practical devices.

A new study has now introduced a far simpler approach to generating this orbital motion in electrons. The key lies in an emerging area of physics centered on chiral phonons.

Chiral Phonons Offer a Breakthrough

For the first time, researchers demonstrated that chiral phonons can directly transfer orbital angular momentum to electrons in a non-magnetic material. This finding removes a major limitation that has long held back orbitronics.

"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," said Dali Sun, physicist at North Carolina State University and co-author of the study. "There are other ways to generate orbital angular momentum, but this method allows for the use of cheaper, more abundant materials."

"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," added Valy Vardeny, distinguished professor in the Department of Physics & Astronomy at the University of Utah and co-author of the study. "Before, it was unimaginable. Now, we've invented a new field, so to speak."

The research was led by North Carolina State University, with contributions from multiple institutions including the University of Utah, and was published on in the journal Nature Physics.

Understanding Chirality and Atomic Motion

The advance relies on how atoms are arranged and how they move inside materials. In solids, atoms form tightly packed lattice structures. In many materials such as metals, these structures are symmetrical, meaning their mirror image looks identical.

Chiral materials are different. In substances like quartz, atoms are arranged in a spiral pattern, similar to the threads of a screw. These structures have a built-in twist, either left- or right-handed, that cannot be superimposed on its mirror image. Human hands are a simple example of chirality.

Atoms in solids are not static. They vibrate in place. In symmetrical materials, this motion tends to be side-to-side. In chiral materials, the twisted structure causes atoms to move in a circular or spiral-like pattern.

Source: ScienceDaily