Abstract
The dynamics of a single-mode semiconductor laser under the optical injection of three signals is theoretically investigated. 3D maps of injection locking are drawn and compared when the master signals are injected at different operating points. The maps show the injection-locking bandwidth, frequency pulling region and secondary locking regions (SLR) in one picture to reveal the complete dynamics of the injected laser. Cascaded SLR are also demonstrated in the maps and explained in terms of other dynamics.