Atom-photon Interfaces

The major aim of NQIT is to create a powerful quantum computing device by interconnecting many simple quantum processors that we have already demonstrated in our laboratories. To do this we need reliable interfaces at the single-quantum level to establish such a connected network.

To do this, we harness the emission of light from non-moving quantum bits stored in single atoms. We have designed special laser pulses that trigger an atom to emit single photons into optical resonators and into a network of optical transmission lines . With an unprecedented level of single-photon emission control we can apply these laser pulses at the push of a button. Together with our collaborators in Bristol, the Oxford team has recently shown that we can now control the coherence properties of these photons so faithfully that we can reliably operate a complex quantum-optical network.

In parallel to this, NQIT researchers in Sussex and in Southampton have been modelling and exploring novel optical resonator designs that significantly improve the photon emission from trapped ions into optical fibres. Meanwhile, our theoreticians in Leeds invented a promising new method for the transfer of quantum states between remote atoms which we are now going to explore in the laboratory.