The rules of quantum mechanics, which typically manifest themselves at the nanoscale, have important consequences for the processing of information. In particular, for certain computational problems, it is possible to devise algorithms that take advantage of 'quantum parallelism' to carry them out much more quickly provided the computer obeys the laws of quantum physics. In practical terms, this means that building a quantum computer would make it possible to solve easily problems that are so hard that they are effectively impossible on a classical computer.
At the LCN, many researchers are studying how to use the spins of electrons and nuclei to represent and manipulate quantum information. We study how to measure individual spins, and how to control them using light and other probes. We also use scanning probe microscopes to implant and contact individual dopant atoms in semiconductors, and spin resonance to manipulate spins. Much of this work is done in close collaboration with the quantum information group in the UCL Department of Physics and Astronomy.
Click below for a list of all LCN Researchers & Research Highlights associated with:
Figure: The entanglement of the qubit electron spins is controlled by exciting a chosen control donor into a spatially more extended state. [courtesy Alan Stonebraker and Marshall Stoneham; doi: 10.1103/Physics.2.34]