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arXiv · 1610.01727

General structure of two-photon S matrix in waveguide quantum electrodynamics systems containing a local quantum system with multiple ground states

Shanshan Xu·Shanhui Fan
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Abstract

We present the general structure of two-photon S matrix for a waveguide coupled to a local quantum system that supports multiple ground states. The presence of the multiple ground states results in a non-commutative aspect of the system with respect to the exchange of the orders of photons. Consequently, the two-photon S matrix significantly differs from the standard form as described by the cluster decomposition principle in the quantum field theory.

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Shanshan Xu, Shanhui Fan. 2016-10-06. General structure of two-photon S matrix in waveguide quantum electrodynamics systems containing a local quantum system with multiple ground states. https://doi.org/10.1103/physreva.95.063809

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