Optical chip enables new approach to quantum computing

Optical chip enables new approach to quantum computing: The technique developed in Bristol uses two identical particles of light (photons) moving along a network of circuits in a silicon chip to perform an experiment known as a quantum walk. Quantum walk experiments using one photon have been done before and can even be modelled exactly by classical wave physics. However, this is the first time a quantum walk has been performed with two particles and the implications are far-reaching.

"Using a two-photon system, we can perform calculations that are exponentially more complex than before," says Prof O'Brien. "This is very much the beginning of a new field in quantum information science and will pave the way to quantum computers that will help us understand the most complex scientific problems."