Control of dynamical instability in semiconductor quantum nanostructures diode lasers: role of phase-amplitude coupling

We numerically investigate the complex nonlinear dynamics for two independently coupled laser systems consisting of (i) mutually delay-coupled edge emitting diode lasers and (ii) injection-locked quantum nano-structures lasers. A comparative study in dependence on the dynamical role of alpha parameter, which determine the phase-amplitude coupling of the optical field, in both the cases is probed. The variation of alpha lead to conspicuous changes in the dynamics of both the systems, which are characterized and investigated as a function of optical injection strength for the fixed coupled-cavity delay time. Our analysis is based on the observation that the cross-correlation and bifurcation measures unveil the signature of enhancement of amplitude-death islands in which the coupled lasers mutually stay in stable phase-locked states. In addition, we provide a qualitative understanding of the physical mechanisms underlying the observed dynamical behavior and its dependence on alpha. The amplitude death and the existence of multiple amplitude death islands could be implemented for applications including diode lasers stabilization.Comment: 9 Pages. arXiv admin note: text overlap with arXiv:1111.2439 by other author

Investigation of Injection-Locked Quantum Cascade Lasers based on Rate equations

International audienceThe modulation properties of optical injection-locked quantum cascade lasers (QCLs) are investigated theoretically via a simple low dimensional rate equation model. It is found that both strong injection level and positive optical frequency detuning increase the modulation bandwidth, while a large linewidth enhancement factor (LEF) contributes to the enhancement of the peak magnitude in the intensity modulation (IM) response. As opposed to conventional injection-locked interband lasers, it is demonstrated that no dip occurs in the QCL's IM response, which is beneficial for a series of broadband microwave photonic applications. Computations also show that the value of the LEF can critically modify both the locking and stability regions on the optical frequency detuning injection level map

Nonlinear dynamics and Modulation Properties of Optically Injected Quantum Cascade Lasers

oral session CB-2 : Quantum Cascade Lasers and Long Wavelength Emitters IIInternational audienceIn this work, we theoretically investigate the nonlinear and modulation properties of injection-locked QC lasers by taking into account the upper and lower subbands as well as the bottom state in the gain stage. In order to obtain the stable injection-locking regime both the saddle-node (SN) and the Hopf bifurcations are studie

Multimode optical feedback dynamics in InAs/GaAs quantum dot lasers emitting exclusively on ground or excited states: transition from short- to long-delay regimes

© 2018 Optical Society of America. Users may use, reuse, and build upon the article, or use the article for text or data mining, so long as such uses are for non-commercial purposes and appropriate attribution is maintained. All other rights are reserved.The optical feedback dynamics of two multimode InAs/GaAs quantum dot lasers emitting exclusively on sole ground or excited lasing states is investigated. The transition from long- to short-delay regimes is analyzed, while the boundaries associated to the birth of periodic and chaotic oscillations are unveiled to be a function of the external cavity length. The results show that depending on the initial lasing state, different routes to chaos are observed. These results are of importance for the development of isolator-free transmitters in short-reach networks

Dispersion uncompensated IM/DD transmissions of 12GHz-wide multi-band OFDM over 100km with a D-EML

International audienceGeneration of optical SSB signals by a D-EML is extended to its whole bandwidth. In an SSB context, 12GHz multi-band OFDM signal is transmitted through 100km intensity modulation/direct detection dispersive channel without frequency fading

Modeling the Injection-Locked Behavior of a Quantum Dash Semiconductor Laser

International audienceUsing the conventional rate equations describing an injection-locked system, a novel modulation response function is derived, which implicitly incorporates nonlinear gain through the free-running relaxation oscillation frequency and damping rate of the slave laser. In this paper, it is shown that the model presented can be used to extract the characteristic parameters of the coupled system from experimental data. The number of fitting parameters in the model is reduced by determining the fundamental slave parameters through the conventional free-running response function; these parameters are considered to be constant during the curve-fitting of the injection-locked system. Furthermore, in order to reduce the number of possible solutions generated during the least-squares-fitting process, the remaining fitting parameters are tightly constrained based on the physical limits of the coupled system. By reducing the number of unknown fitting parameters and constraining the remaining terms, a stronger confidence in the extracted parameters is achieved. Using a series of response curves measured from an injection-locked quantum dash laser, characteristic parameters of the system are extracted and validity of the model is examined. The verified model is used to analyze the impact of the linewidth enhancement factor on the characteristics of the response function in the microwave domain

Tuning of the critical feedback level in 1.55-μm quantum dash semiconductor laser diodes

International audienceThe onset of the coherence collapse (CC) regime, which is incompatible with data transmission, is investigated both theoretically and experimentally in a 1.55-um InAs/InP quantum dash semiconductor laser. It is numerically shown that the filling from the excited state produces an additional term, which accelerates the route to chaos. This contribution can be seen as a perturbation that reduces the overall CC threshold

rf linewidth reduction in a quantum dot passively mode-locked laser subject to external optical feedback

International audienceThe effect of external optical feedback on an InAs/GaAs quantum dot passively mode-locked laser is investigated. The rf linewidth narrows from 8 KHz in the free-running situation to a value as low as 350 Hz under relatively low feedback. The rf linewidth characterization under resonant feedback at a multiple of the laser cavity length validates the prediction of a previous numerical simulation. It is also confirmed that the integrated rms timing jitter varies as the square root of the rf linewidth. The results are promising for the development of compact, monolithic semiconductor mode-locked lasers as low noise optoelectronic oscillators

Optical feedback instabilities in a monolithic InAs/GaAs quantum dot passively mode-locked laser

International audienceThe impact of optical feedback on the direct performance of a monolithic InAs/GaAs quantum dot passively mode-locked laser intended for applications such as multigigahertz interchip/intrachip clock distribution is experimentally investigated. Evaluation of the feedback resistance is an important feature, as the laser is to be monolithically integrated on chip with other devices, in which case optical isolation is difficult. This work shows that a feedback level on the order of −24 dB is detrimental for mode-locking operation, enhancing noise in the rf electrical signal, strongly narrowing the useful mode-locking region as well as causing central frequency shift, and severe instabilities

Unveiling the dynamical diversity of quantum dot lasers subject to optoelectronic feedback

This paper investigates experimentally and numerically the nonlinear dynamics of an epitaxial quantum dot laser on silicon subjected to optoelectronic feedback. Experimental results showcase a diverse range of dynamics, encompassing square wave patterns, quasi-chaotic states, and mixed waveforms exhibiting fast and slow oscillations. These measurements unequivocally demonstrate that quantum dot lasers on silicon readily and stably generate a more extensive repertoire of nonlinear dynamics compared to quantum well lasers. This pronounced sensitivity of quantum dot lasers to optoelectronic feedback represents a notable departure from their inherent insensitivity to optical feedback arising from reflections. Moreover, based on the Ikeda-like model, our simulations illustrate that the inherent characteristics of quantum dot lasers on silicon enable rapid and diverse dynamic transformations in response to optoelectronic feedback. The emergence of these exotic dynamics paves the way for further applications like integrated optical clocks, optical logic, and optical computing