Professor Jeremy O’Brien, Director of the University of Bristol’s Centre for Quantum Photonics, and his Japanese colleagues have demonstrated a quantum logic gate acting on four particles of light — photons. The researchers believe their device could provide important routes to new quantum technologies, including secure communication, precision measurement, and ultimately a quantum computer — a powerful type of computer that uses quantum bits (qubits) rather than the conventional bits used in today’s computers.
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Optical circuit enables new approach to quantum technologies