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arXiv · 2202.06992

Deterministic Photon Sorting in Waveguide QED Systems

Fan Yang·Mads M. Lund·Thomas Pohl·Peter Lodahl·Klaus Mølmer
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Abstract

Sorting quantum fields into different modes according to their Fock-space quantum numbers is a highly desirable quantum operation. In this Letter, we show that a pair of two-level emitters, chirally coupled to a waveguide, may scatter single- and two-photon components of an input pulse into orthogonal temporal modes with a fidelity $\gtrsim 0.9997$. We develop a general theory to characterize and optimize this process and observe an interesting dynamics in the two-photon scattering regime: while the first emitter gives rise to a complex multimode field, the second emitter recombines the field amplitudes and the net two-photon scattering induces a self-time reversal of the pulse mode. The presented scheme can be employed to construct logic elements for propagating photons, such as a deterministic nonlinear-sign gate with a fidelity $\gtrsim 0.9995$

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Fan Yang, Mads M. Lund, Thomas Pohl, Peter Lodahl, Klaus Mølmer. 2022-02-14. Deterministic Photon Sorting in Waveguide QED Systems. https://doi.org/10.1103/physrevlett.128.213603

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