Map of Mode Hopping Associated with Modulated Laser Diode Under Feedback and Injection

Abstract

A new simple technique for narrow-linewidth and wavelength-tunable laser is experimentally satisfied. The technique is based on employing nonlinearities arise with laser feedback and injection. The main effect observed and controlled is the mode hopping (MH) within other nonlinearities. In this situation mixed optoelectronical feedback (OEFB) and optical injection from another identical type laser simultaneously, plays the role of controller. These results show that no need of using a Fiber Bragg Grating. As a well-known alternative technique used earlier to build a tunable laser. The map of validity for this effect and parameters affecting the laser output are all investigated. This technique enhances modulation index for the slave laser to be 100% and employs mode hoping generated in it for tuning output lasing frequency. This is by controlling either master laser detuning or injection strength or both. Also, by controlling slave laser optoelectronic feedback time delay (by a variable RF attenuator) or (and) nonlinear contribution for this by introducing a nonlinear function into the detected signal. Bidirectional (mutual) and unidirectional injection systems are experimented. In the first system both lasers multi-lasing in general synchronization manner, while in the last system, injector (master) laser stays immune from slave dynamics.