Dynamics Of Vcsels Subject To Optical Injection And Positive Optoelectronic Feedback

Nonlinear dynamics of SLs under one external perturbation have attracted much attention due to its potential applications such as chaotic secure communications, laser radar, Microwave Photonics and other fields. The pertinent findings have been widely reported. Recently, the dynamics characteristics of a SL subject to more than one perturbation have attracted more and more attention. Existing research results show that the SLs with a few of perturbation have more rich and complex behavior of dynamic. With controlling the number of perturbation parameters. Recently, the dynamics characteristics of a SL subject to more than one perturbation is edge-emitting lasers. But the research in this area is still very lacking for vertical cavity surface emitting lasers (VCSELs), which is booming in recent years. Because the VCSEL has many advantages, such as a low-threshold current, single-longitudinal-mode operation, circular output beam and easy integration into two dimension arrays and so on. Therefore, it is very important to study the dynamics of VCSEL, which has more than one perturbation.Based on the spin-flip model (SFM), we theoretically investigate the dynamics of a vertical-cavity surface-emitting laser (VCSEL) subject to optical injection and positive optoelectronic feedback. The results show that, under the joint actions of positive optoelectronic feedback and optical injection from a master VCSEL (M-VCSEL), two polarization modes of a slave VCSEL (S-VCSEL) will behave rich dynamic states such period one, period two, multi-period and chaos, and the evolution routes of these states are different for two polarization modes. Mapping of dynamic region as a function of feedback strength/and injection strength (?) is varied with frequency detuning between M-VCSEL and S-VCSEL Δv (=vm-vs, where vm and vs are the free-running frequencies of M-VCSEL and S-VCSEL, respectively). Compared with the case for zero or negative frequency detuning, the region of chaotic state is expanded significantly under positive Δv. For a fixed Δv, the influences of f and η on the chaotic bandwidth of S-VCSEL have been discussed. Through selecting proper f and η, chaotic bandwidth of S-VCSEL can be improved obviously.