A team of physicists at the University of Toronto (U of T) have taken a step toward making the essential building block of quantum computers out of pure light.
Their advance, described in a paper published this week in Nature Physics, has to do with a specific part of computer circuitry known as a “logic gate.”
Logic gates perform operations on input data to create new outputs. In classical computers, logic gates take the form of diodes or transistors. But quantum computer components are made from individual atoms and subatomic particles. Information processing happens when the particles interact with one another according to the strange laws of quantum physics.
Light particles – known as “photons” – have many advantages in quantum computing, but it is notoriously difficult to get them to interact with one another in useful ways. This experiment demonstrates how to create such interactions.