arXiv:2009.08602 · Physical Review A

Optimal two-photon excitation of bound states in non-Markovian waveguide QED

Rahul Trivedi, Daniel Malz, Shuo Sun, Shanhui Fan, Jelena Vuckovic A

Published Jul 7, 2021• 17 citations

Abstract

Bound states arise in waveguide QED systems with a strong frequency-dependence of the coupling between emitters and photonic modes. While exciting such bound-states with single-photon wave-packets is not possible, photon-photon interactions mediated by the emitters can be used to excite them with two-photon states. In this Letter, we use scattering theory to provide upper limits on this excitation probability for a general non-Markovian waveguide QED system and show that this limit can be reached by a two-photon wave packet with vanishing uncertainty in the total photon energy. Furthermore, we also analyze multi-emitter waveguide QED systems with multiple bound states and provide a systematic construction of two-photon wave packets that can excite a given superposition of these bound states. As specific examples, we study bound-state trapping in waveguide QED systems with single and multiple emitters and a time-delayed feedback.

DOI: 10.1103/physreva.104.013705

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