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arXiv · 2112.11328

Passive quantum phase gate for photons based on three level emitters

Björn Schrinski·Miren Lamaison·Anders S. Sørensen
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Abstract

We present a fully passive method for implementing a quantum phase gate between two photons travelling in a one-dimensional wave guide. The gate is based on chirally coupled emitters in a three-level $V$ configuration, which only interact through the photon field without any external control fields. We describe the (non-)linear scattering of the emerging polariton states and show that for near resonant photons the scattering dynamics directly implements a perfect control phase gate between the incoming photons in the limit of many emitters. For a finite number of emitters we show that the dominant error mechanism can be suppressed by a simple frequency filter at the cost of a minor reduction in the success probability. We verify the results via comparison with exact scattering matrix theory and show that the fidelity can reach values $\mathcal{F}\sim99\%$ with a gate success probability of $>99\%$ for as few as 8 emitters.

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Björn Schrinski, Miren Lamaison, Anders S. Sørensen. 2021-12-21. Passive quantum phase gate for photons based on three level emitters. https://doi.org/10.1103/physrevlett.129.130502

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