Computing with a quantum trick

Quantum computing is almost a sure thing in the not-too-distant future. Physicists from the Max Planck Institute of Quantum Optics in Garching have developed a novel quantum gate, an essential component of quantum computers ("A quantum gate between a flying optical photon and a single trapped atom").

A future quantum computer would be able to handle certain types of tasks far faster than a conventional computer. As a central element of their quantum gate, the Max Planck physicists are using an atom trapped between two mirrors of a resonator. Moreover, by reflecting the atom off the resonator with a photon, they are able to switch the state of the photon. Moreover, the computational operation can entangle the atom with the photon. When quantum particles are entangled, their properties become interdependent. Entanglement opens up whole new horizons in information processing. The quantum gate recently presented by the Garching-based physicists makes it possible to design quantum networks in which information is transferred between parallel quantum processors in the form of photons.