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arXiv · 1405.6117

Room-Temperature Quantum Memory for Polarization States

Connor Kupchak·Thomas Mittiga·Bertus Jordaan·Mehdi Namazi·Christian Nölleke·Eden Figueroa
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Abstract

An optical quantum memory is a stationary device that is capable of storing and recreating photonic qubits with a higher fidelity than any classical device. Thus far, these two requirements have been fulfilled in systems based on cold atoms and cryogenically cooled crystals. Here, we report a room-temperature quantum memory capable of storing arbitrary polarization qubits with a signal-to-background ratio higher than 1 and an average fidelity clearly surpassing the classical limit for weak laser pulses containing 1.6 photons on average. Our results prove that a common vapor cell can reach the low background noise levels necessary for quantum memory operation, and propels atomic-vapor systems to a level of quantum functionality akin to other quantum information processing architectures.

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Connor Kupchak, Thomas Mittiga, Bertus Jordaan, Mehdi Namazi, Christian Nölleke, Eden Figueroa. 2014-05-23. Room-Temperature Quantum Memory for Polarization States. https://arxiv.org/abs/1405.6117

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