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arXiv · 1512.07374

Ultra-low-noise room-temperature quantum memory for polarization qubits

Mehdi Namazi·Connor Kupchak·Bertus Jordaan·Reihaneh Shahrokhshahi·Eden Figueroa
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Abstract

Here we show an ultra-low noise regime of operation in a simple quantum memory in warm Rb atomic vapor. By modelling the quantum dynamics of four-level room temperature atoms, we achieve fidelities >90% for single-photon level polarization qubits, clearly surpassing any classical strategy exploiting the non-unitary memory efficiency. This is the first time such important threshold has been crossed with a room temperature device. Additionally we also show novel experimental techniques capable of producing fidelities close to unity. Our results demonstrate the potential of simple, resource-moderate experimental room temperature quantum devices.

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Mehdi Namazi, Connor Kupchak, Bertus Jordaan, Reihaneh Shahrokhshahi, Eden Figueroa. 2017-06-04. Ultra-low-noise room-temperature quantum memory for polarization qubits. https://doi.org/10.1103/physrevapplied.8.034023

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