Mesoscopic superposition states of photons can be prepared in three cavities interacting with the same two-level atom. By periodically modulating the three cavity frequencies around the transition frequency of the atom with 2π/3 phase difference, the time reversal symmetry is broken and an optical circulator is generated with chiralities depending on the quantum state of the atom. A superposition of the atomic states can guide photons from one cavity to a mesoscopic superposition of the other two cavities. The physics can be understood in a finite spin-orbit-coupled Fock-state lattice where the atom and the cavities carry the spin and the orbit degrees of freedom, respectively. This scheme can be realized in circuit QED architectures and provides a new platform for exploring quantum information and topological physics in novel lattices.
@article{arxiv.1602.08009,
title = {Mesoscopic Superposition States Generated by Synthetic Spin-orbit Interaction in Fock-state Lattices},
author = {Da-Wei Wang and Han Cai and Ren-Bao Liu and Marlan O. Scully},
journal= {arXiv preprint arXiv:1602.08009},
year = {2016}
}