Quantum gates

You better count on quantum information in the 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 future quantum computer would be able to handle certain types of tasks far faster than any classical computer. As a central element of their quantum gate, the Max Planck physicists are using an atom trapped between two mirrors of a resonator. By reflecting the photon off the resonator with the atom, they are able to switch the state of the photon. Moreover, the gate 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 remote quantum processors in the form of photons.