Nonlinear Dynamics Of Optical Injected 1550nm VCSELs Subject To Negative Optoelectronic Feedback

With the advent of the optoelectronic era, semiconductor laser has become one of the fastest growing and widely used laser light sources in the world. Especially, semiconductor lasers have attracted considerable attention because their potential application prospect in some fields such as optical storage, optical interconnection, optical communications and optoelectronic display. Compared with other semiconductor lasers, vertical cavity surface emitting lasers(VCSELs), as a typical representative of the new type of quantum well semiconductor lasers, have become a focus because of some advantages such as small volume, low threshold current, a single-longitudinal-mode operation, the small far-field divergence angle, high dynamic modulation frequency, easy to couple optical fiber and so on. It is well known that VCSELs with free-running or external perturbation can exhibit rich nonlinear dynamical behaviors such as Period-one(P1), Period-two(P2), Quasi-periodic Oscillation(QP), Chaos(CO) dynamics and so on. Moreover, these nonlinear dynamical behaviors can be widely applicated in optical information processing, optical chaotic secure communications, high-frequency microwave technology, high-speed true random accessing technology, et al. Previously relative studies mostly concentrated on the material system, structure and performance of the short-wavelength(< 1μm) VCSELs, and the nonlinear dynamical characteristics of the free running VCSELs or the VCSELs subject to external perturbations including optical injection, optical feedback, optoelectronic feedback have also been studied. In recent years, with the improvement of production technology, the long-wavelength(> 1μm) VCSELs has possessed better performance and shown great application potential in communication, information processing and optical microwave. Therefore, relative researches about the long-wavelength VCSELs should attract more attention.Considering these practical values of the long-wavelength VCSELs, based on the Spin-flip Model(SFM), the nonlinear dynamical characteristics of a 1550 nm VCSEL subject to orthogonally polarized beams injection and negative optoelectronic feedback were theorectically investigated. The results show that, for a free-running 1550 nm VCSEL lasing at the Y linear polarization mode, under suitable injection strength and frequency detuning, 1550 nm orthogonally polarized optical injected VCSEL can exhibit many nonlinear dynamic behaviors such as Stable State, P1, P2, Multi-period, CO, Stable Injection Locking(SIL) and polarization switching(PS) phenomena. Then, after introducing the negative optoelectronic feedback, some new nonlinear dynamic behaviors, such as Double Frequency Quasi-periodic Oscillation(Q2), Triple Frequency Quasi-periodic Oscillation(Q3), can be observed. For a certain feedback delay, the dynamic distribution regions of the orthogonally polarized optical injected VCSEL outputs in the parameter space of injection strength and frequency detuning will be influenced by the optoelectronic feedback strength. Under a certain optoelectronic feedback strength, for relatively small injection strength, the feedback delay has an obvious effect on the dynamic distribution regions in the parameter space of injection strength and frequency detuning. For relatively larger injection strength, the delay time has little effect on the dynamic distribution regions and the laser almost operates at P1 or SIL state.