Indefinite causal order in cavity quantum electrodynamics
The paper investigates Indefinite Causal Order (ICO) as a resource for quantum information processing in cavity quantum electrodynamics (cQED). ICO allows entanglement between two distant fields that never directly interact, and it outperforms fixed-order scenarios by always generating significant entanglement when cavities are in the vacuum state. Furthermore, ICO enables the complete interchange of one photon between both cavities without altering the atomic state.