Chinese Physics B

Single-photon scattering and quantum entanglement of two giant atoms with azimuthal angle differences in a waveguide system

Jin-Song 劲松 Huang 黄, Hong-Wu 红武 Huang 黄, Yan-Ling 艳玲 Li 李, Zhong-Hui 中辉 Xu 徐

Published Feb 2, 2024• 3 citations

Abstract

We theoretically investigate coherent scattering of single photons and quantum entanglement of two giant atoms with azimuthal angle differences in a waveguide system. Using the real-space Hamiltonian, analytical expressions are derived for the transport spectra scattered by these two giant atoms with four azimuthal angles. Fano-like resonance can be exhibited in the scattering spectra by adjusting the azimuthal angle difference. High concurrence of the entangled state for two atoms can be implemented in a wide angle-difference range, and the entanglement of the atomic states can be switched on/off by modulating the additional azimuthal angle differences from the giant atoms. This suggests a novel handle to effectively control the single-photon scattering and quantum entanglement.

DOI: 10.1088/1674-1056/ad2508

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