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arXiv · 0808.1666

Perfect excitation of a matter qubit by a single photon in free space

Magdalena Stobińska·Gernot Alber·Gerd Leuchs
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Abstract

We propose a scheme for perfect excitation of a single two-level atom by a single photon in free space. The photon state has to match the time reversed photon state originating from spontaneous decay of a two-level system. We discuss its experimental preparation. The state is characterized by a particular asymmetric exponentially-shaped temporal profile. Any deviations from this ideal state limit the maximum absorption. Although perfect excitation requires an infinite amount of time we demonstrate that there is a class of initial one-photon quantum states which can achieve almost perfect absorption even for a finite interaction time. Our results pave the way for realizing perfect coupling between flying and stationary qubits in free space thus opening a possibility for building scalable quantum networks.

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Magdalena Stobińska, Gernot Alber, Gerd Leuchs. 2009-01-13. Perfect excitation of a matter qubit by a single photon in free space. https://doi.org/10.1209/0295-5075%2F86%2F14007

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