Controlling electronic current is essential to modern electronics, as data and signals are transferred by streams of electrons controlled at high speed. Demands on transmission speeds are also increasing as technology develops. Physicists at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have succeeded in switching on a current with a desired direction in graphene using a single laser pulse within a femtosecond—a femtosecond corresponds to the millionth part of a billionth of a second. This is more than a thousand times faster than the most efficient transistors today.