The present invention is a photonic logic circuit for multimode optical signals. The device includes a laser cavity having at least four conduits, the combination forming a substantially X-shaped construction. An output is attached to each conduit for transmission of the optical signals from the cavity. At least one input is connected to the laser cavity. The input is connected to an upper or lower edge of the laser cavity. These are the edges that do not include conduits. A bias contact is connected to the cavity and the two lower conduits. The bias contact is used to pump the photonic device. Preset contacts are attached to each of the upper two conduits and their respective outputs. The preset contacts are used to control the logic function of the photonic logic device. Altering current pump settings between the respective contacts controls the direction of lasing between outputs of the photonic device and the logic function performed.