Ultra pure diamond pushes quantum computing work forward

The team, in a letter to Nature Physics, says its latest results demonstrate all basic elements of a room temperature quantum register. This implies the team has been able to control and read information as needed for a practical computer. The results are part of a three year project called Engineered Quantum Information in Nanostructured Diamond, or EQUIND. Its aim is to establish whether specific optical features identified in diamond can be used as the basic elements for quantum computers and single photon sources. According to the team, a critical step towards scalability is to develop a technique allowing mutual coupling of individual optically addressable quantum systems. Its letter says recent experiments have shown the spins of two separate nitrogen vacancy (NV) defects in diamond can be coupled and entangled. The NV defect is created by substituting a nitrogen atom for a carbon atom in the diamond structure and be creating a vacant site alongside the nitrogen atom. When this is accomplished, the defect can exhibit two charge states. At the heart of the research is extremely pure single crystal diamond developed and supplied by E6 Technologies Division, which has developed an ultra high purity single crystal diamond using chemical vapour deposition (CVD). E6 has delivered single crystal CVD diamond in which the background spin impurity is very low. According to Dr Daniel Twitchen, E6 Technologies' principal scientist, this has been achieved by controlling both the isotopic purity and point defect density.