Researchers showed that two-color laser pulses can temporarily transform graphene into a Floquet topological state and steer electrons within it. By combining circularly polarized light with its second harmonic, they controlled both the direction and strength of photocurrents and observed an all-optical anomalous Hall effect without a magnetic field. The approach could enable ultrafast control of transient topological states for future electronics and information processing.

https://www.nature.com/articles/s41567-026-03429-7