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arXiv · 2209.03418

Single photons versus coherent state input in waveguide quantum electrodynamics: light scattering, Kerr and cross-Kerr effect

Athul Vinu·Dibyendu Roy
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Abstract

While the theoretical studies in waveguide quantum electrodynamics predominate with single-photon and two-photon Fock state (photon number states) input, the experiments are primarily carried out using a faint coherent light. We create a theoretical toolbox to compare and contrast linear and nonlinear light scattering by a two-level or a three-level emitter embedded in an open waveguide carrying Fock state or coherent state inputs. We identify rules to compare light transport properties, the Kerr, and cross-Kerr nonlinearities of the medium for the two types of inputs. A generalized description of the Kerr and cross-Kerr effect for different types of inputs is formulated to compare the Kerr and cross-Kerr nonlinearity between two photons in these models.

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Athul Vinu, Dibyendu Roy. 2022-09-07. Single photons versus coherent state input in waveguide quantum electrodynamics: light scattering, Kerr and cross-Kerr effect. https://doi.org/10.1103/physreva.107.023704

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