Dual-channel all-optical switching with tunable frequency in a five-level double-ladder atomic system

A scheme of five-level double-ladder-type atomic system is proposed with the aim of implementing dual-channel all-optical switching. Two transitions in the five-level atomic medium independently interact with the two orthogonally (circularly) polarized components from a weak linearly-polarized probe beam, while two other atomic transitions are coherently driven by a control beam and a switching signal beam. We demonstrate that the switching on/off of two orthogonally polarized beams at different frequencies can be achieved by adjusting the magnitude of the external magnetic field, which expands the frequency range of an optical signal switching operation and may improve its practicability.

Research Highlights
► The implementation of a dual-channel all-optical switching is investigated.
► The scheme may improve the communication capacity comparing with one-way switching.
► The switched-signal frequency can be tuned by adjusting the magnetic field strength.