Researchers harness magnetism and quantum topology for next-generation devices
Scientists have discovered a material that switches between metal and insulator states while maintaining magnetic properties—a feat that could unlock new quantum computing and electronics applications. The discovery, published in Nature Communications, shows how electron interactions can control this switching, offering a pathway to build devices that leverage magnetism and topological physics simultaneously.
Originaltitel: Topological metal-insulator transition within the ferromagnetic state
Abstract A major challenge in condensed matter physics is integrating topological phenomena with correlated electron physics to leverage both types of states for next-generation quantum devices. Metal-insulator transitions are central to bridging these two domains while simultaneously serving as on-off switches for electronic states. Here, we demonstrate how the prototypical material of K 2 Cr 8 O 16 undergoes a ferromagnetic metal-insulator transition accompanied by a change in band topology. Through inelastic x-ray and neutron scattering experiments combined with first-principles theoretical calculations, we show that this transition is not driven by a Peierls mechanism, given the lack of phonon softening. Instead, we establish the transition as a topological metal-insulator transition within the ferromagnetic phase with potential axionic properties, where electron correlations play a key role in stabilizing the insulating state. These results reveal how a metal-insulator transition provides a pathway through which magnetism, topology, and electronic correlations interact.