A qubit candidate shines brighter

In the race to design the world's first universal quantum computer, a special kind of diamond defect called a nitrogen vacancy (NV) center is playing a big role. NV centers consist of a nitrogen atom and a vacant site that together replace two adjacent carbon atoms in diamond crystal. The defects can record or store quantum information and transmit it in the form of light, but the weak signal is hard to identify, extract and transmit unless it is intensified.

Now a team of researchers at Harvard, the University of California, Santa Barbara and the University of Chicago has taken a major step forward in effectively enhancing the fluorescent light emission of diamond nitrogen vacancy centers -- a key step to using the atom-sized defects in future quantum computers. The technique, described in the journal Applied Physics Letters, from AIP Publishing, hinges on the very precise positioning of NV centers within a structure called a photonic cavity that can boost the light signal from the defect.