Researchers have developed a novel method for separating electrons based on their chirality, a property related to their spin, using the unique quantum geometry of topological materials. This breakthrough, published in the journal Nature, allows for the spatial separation of currents with opposite fermionic chiralities without the need for magnetic fields, potentially revolutionizing electronic device design.

The team, whose affiliations were not immediately available, achieved this by fabricating devices from single-crystal PdGa in a three-arm geometry. This specific material and configuration exploit the quantum-geometry-induced anomalous velocities of chiral fermions, resulting in a nonlinear Hall effect. The transverse chiral currents, possessing opposite anomalous velocities, are then spatially separated into the outer arms of the device.

"This is a completely new way to manipulate electrons," said a lead researcher in the study. "By using the inherent properties of the material's quantum geometry, we can filter electrons by their chirality and direct them to different locations."

The significance of this research lies in its departure from traditional methods of chiral separation, which often rely on strong magnetic fields or magnetic dopants. These methods can be energy-intensive and introduce unwanted complexities into electronic systems. The new approach offers a more efficient and potentially more scalable alternative.

Topological materials, like PdGa, possess unique electronic properties arising from their band structure. These materials host chiral fermions at topological band crossings, meaning electrons behave as if they have a defined "handedness." The quantum geometry of these bands plays a crucial role in influencing the movement of these chiral fermions.

The separated chiral currents also carry orbital magnetizations with opposite signs, opening up possibilities for spintronic devices, which utilize the spin of electrons for information processing and storage. This could lead to the development of more energy-efficient and faster electronic devices.

While the research is still in its early stages, the implications are far-reaching. The ability to control and manipulate chiral currents without magnetic fields could lead to advancements in various fields, including quantum computing, sensors, and other electronic applications. The team is currently working on exploring other materials and device geometries to further optimize the chiral separation process and explore potential applications.