Hans-Andreas Engel and Daniel Loss of the University of Basel in Switzerland have explained how to make a device called a spin-parity meter, quantum computing's equivalent of the transistor.
Although they have worked out how to build one, they have not got as far as putting one together.
Quantum computers substitute information encoded using the magnetic state
Engel and Loss have shown how it is possible to measure the spins of electrons without disturbing them and builds on work done by David DiVincenzo and his team at IBM. Their work looks at how computing can be performed by mapping data as it spreads through a network of components and is designed to avoid pitfalls in earlier quantum computing theories that treated data in a more conventional, circuit-base way.
More information on recent quantum computing developments can be read in this Nature article.