New Artificial Atom Could be a Breakthrough in Quantum Computing

The device, engineered to behave like a single atom, was made using integrated circuit fabrication techniques. It's the first experimental result in a field Yale professors Robert Schoelkopf and Steven Girvin have dubbed "Circuit Quantum Electrodynamics."

These superconducting devices can operate as qubits, the basic element of information storage in the field of quantum computing. There is evidence that their qubit was coupling to a microwave photon, sharing energy in much the same way electrons are shared when two atoms combine to form a molecule. Suggested names for the new, combined state are phobit or quton.

Qutons were first made about 12 years ago. But, by using artificial atoms instead of real ones for their qubits, and by using microwave transmission lines instead of optical cavities, the Yale physicists were able to shrink a roomful of experimental apparatus onto a chip that measures less than 1 sq cm. They have also improved the coupling between the resonator and the "atom" by a factor of about 1,000. This will help explore the fundamental inter-actions of light and matter. Soon they will try to control several qubits on one chip, using photons to connect them together in a prototype architecture for quantum computing and quantum cryptography.