A strange quantum metal just rewrote the rules of electricity

In a remarkable leap for quantum physics, researchers in Japan have uncovered how weak magnetic fields can reverse tiny electrical currents in kagome metals—quantum materials with a woven atomic structure that frustrates electrons into forming complex patterns. These reversals amplify the metal’s electrical asymmetry, creating a diode-like effect up to 100 times stronger than expected. The team’s theoretical explanation finally clarifies a mysterious phenomenon first observed in 2020, revealing that quantum geometry and spontaneous symmetry breaking are key to this strange behavior.

Quantum metals are a unique group of materials where quantum behaviors, typically confined to the atomic scale, become strong enough to shape how electricity behaves across the entire material.