One-way superconductor opens door to resistance-free computing

A research team at Delft University of Technology has demonstrated one-way superconductivity without magnetic fields. This experimental result, which was long thought to be impossible, could clear a path to speeding up conventional computing by a factor of 300-400 while saving energy. “If the 20th century was the century of semiconductors, the 21st can become the century of the superconductor,” commented Mazhar Ali, associate professor at TU Delft and lead author of the study published in Nature.

It’s impossible to build a computer without having control over the direction in which currents flow. That’s why modern electronics are based on semiconductors; these allow for one-way electrical conduction. The textbook example of this is the pn junction, in which a semiconductor with an excess of holes is connected to one with extra electrons. Due to the interaction of the charges, a potential builds up, making it harder for an electron to travel in one direction than the other. Pn junctions are the building blocks of several electronic devices, including diodes, transistors and LEDs. The diode, which conducts primarily in one direction, consists of a single pn junction.