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August 19, 2003

Using 3 Qubits instead of 2

There have been reports about some interesting quantum computing progress by researchers from UCL and Oxford. Simon Benjamin and Sougato Boise have proposed a radically different quantum computer design that no longer requires on-off interactions between the qubits storing the states. Instead of relying on metal electrodes to control the interaction between two qubits sharing superposition, the new design uses a third qubit that is attuned to a different energy frequency. The middle electron responds differently to energy frequencies than does its neighbors on both sides, and the device would be able to complete all necessary logic functions necessary for quantum computing.

The Technology Research News magazine reports on this in its August 13/20 issue.

The report by the researchers can be found in the Physical Review Letters, it quite readable also for non-physicists or academics, just skip the Greek characters and you'll catch most of the ideas.

Quantum Computing with an Always-On Heisenberg Interaction
Simon C. Benjamin and Sougato Bose, Physical Review Letters, 20 June 2003, Volume 90, Number 24

Posted by Werner Vogels at August 19, 2003 04:40 PM