TU Delft demonstrates spin transport in graphene without magnets

Researchers at Delft University of Technology have succeeded in generating spin currents in graphene using the quantum spin Hall effect, without the need for external magnetic fields. By stacking graphene on a monolayer of the magnetic semiconductor CrPS₄ (chromium thiophosphate), they induced a topological spin state that allows spin transport over tens of micrometers, even in the presence of disorder.

Spin is a quantum mechanical property of electrons, which is like a tiny magnet carried by the electrons, pointing up or down. It’s possible to leverage spin to transfer and process information. Such spintronic devices hold promise for faster and more energy-efficient electronics, as well as for quantum computing and advanced memory devices.

The latest findings, published in Nature Communications, provide a new and more practical platform for exploring two-dimensional spintronics. “The detection of quantum spin currents in graphene has always required large magnetic fields that are practically impossible to integrate on-chip. Thus, the fact that we’re now achieving the quantum spin currents without the need for external magnetic fields opens the path for the future applications of these quantum spintronic devices,” says the paper’s first author Talieh Ghiasi.