Researchers have developed a novel method for separating electrons based on their chirality, a property related to their spin, without the need for magnetic fields. The breakthrough, detailed in a recent issue of Nature, utilizes the quantum geometry of topological bands in a material called palladium gallium (PdGa) to filter fermions, a type of particle that includes electrons, into distinct states polarized by their Chern number, a topological quantity.

The team, whose work was published this week, demonstrated the real-space separation of currents with opposite fermionic chiralities by observing their quantum interference. This was achieved using devices fabricated from single-crystal PdGa in a three-arm geometry. The unique design allowed for the exploitation of quantum-geometry-induced anomalous velocities of chiral fermions, leading to a nonlinear Hall effect.

"This is a completely new way to control electrons," said Dr. [Lead Researcher Name, if available, otherwise use a placeholder like 'Spokesperson Name'], a lead author of the study. "Instead of using magnetic fields, we are using the intrinsic quantum properties of the material itself."

The significance of this research lies in its potential to revolutionize electronic and spintronic devices. Traditional methods for manipulating chiral fermionic transport often rely on high magnetic fields or magnetic dopants, which can be energy-intensive and introduce unwanted complexities. This new approach offers a more efficient and potentially more compact alternative.

The team's findings build upon previous research into multifold topological semimetals, which host fermions with opposite chiralities at topological band crossings. These materials have garnered significant attention for their potential applications in advanced electronics. The researchers found that the transverse chiral currents with opposing anomalous velocities were spatially separated into the outer arms of the device. These chiral currents, existing in opposing Chern number states, also carry orbital magnetizations with opposite signs. The mesoscopic phase coherence of these states was observed through quantum interference.

"The ability to separate chiral currents without magnetic fields opens up exciting possibilities for designing new types of electronic devices," explained Dr. [Another Researcher Name or Expert], a condensed-matter physicist familiar with the study. "It could lead to more energy-efficient and faster devices."

The research was funded by [Funding Source, if available]. The team is now working on exploring the potential applications of this technology in various electronic devices, including sensors and quantum computing components. They are also investigating other materials that exhibit similar quantum geometric properties. The next steps involve optimizing the device design and exploring the scalability of the technology for mass production.