Single-photon embedded eigenstates in coupled cavity-atom systems

TL;DR

This paper explores how atomic nonlinearities enable the creation and control of single-photon embedded eigenstates in coupled cavity-atom systems, overcoming reciprocity limitations for photon trapping.

Contribution

It demonstrates that atomic nonlinearities can support single-photon embedded eigenstates that are excitable from outside, a novel approach in nanophotonics.

Findings

Photon trapping and release can be highly efficient.

Atomic nonlinearities enable excitation of embedded eigenstates.

Loss effects and experimental pathways are discussed.

Abstract

Confining light in open structures is a long-sought goal in nanophotonics and cavity quantum electrodynamics. Embedded eigenstates provide infinite lifetime despite the presence of available leakage channels, but in linear time-invariant systems they cannot be excited from the outside, due to reciprocity. Here, we investigate how atomic nonlinearities may support single-photon embedded eigenstates, which can be populated by a multi-photon excitation followed by internal relaxation. We calculate the system dynamics and show that photon trapping, as well as the reverse release process, can be achieved with arbitrarily high efficiencies. We also discuss the impact of loss, and a path towards the experimental verification of these concepts.