Optoelectronic Feedback Research Articles

Busse Balloon for Optical Frequency Combs From a Semiconductor Laser With Time-Delayed Optoelectronic Feedback

Busse Balloon for Optical Frequency Combs From a Semiconductor Laser With Time-Delayed Optoelectronic Feedback

Broadband stepped-frequency radar waveform generation by Fourier domain mode-locking period-one laser dynamics.

A stepped-frequency (SF) radar waveform generation method based on Fourier domain mode-locking (FDML) period-one laser dynamics is proposed and demonstrated. By fast controlling the optical injection strength of a semiconductor laser through electro-optical modulation, a broadband SF signal is generated. By further introducing an optoelectronic feedback loop with its round trip time delay matched with the temporal period of the SF signal, FDML is enabled through which the frequency stability, accuracy, and in-band signal-to-noise ratio are greatly improved. In the experiment, SF signals with a bandwidth of 6 GHz (12-18 GHz) and a frequency step of 150 MHz are generated. By comparing the qualities of signals generated with and without FDML, advantages of the proposed SF signal generation method are verified. Based on the proposed SF signal generation method, high-resolution inverse synthetic aperture radar (ISAR) imaging is also demonstrated, in which the 2D imaging resolution reaches 2.6 cm × 3.82 cm.

Discovery of dissipative microwave photonic soliton molecules in dual-bandpass optoelectronic oscillator

Optoelectronic oscillators (OEOs), which have attracted extensive studies in the past decades, are high quality-factor optoelectronic feedback loops for generating various ultra-pure microwave signals. In essence, OEOs are also dissipative nonlinear systems with multiple timescale characteristics and abundant nonlinearities, which open the possibilities for exploring localized dissipative solitary waves. In this paper, we demonstrate a new-class temporal dissipative soliton, i.e., dissipative microwave photonic soliton molecule (DMPSM), in a dual-bandpass OEO. Both the numerical simulation and experiment are conducted to reveal the physical mechanism of DMPSM generation and to evaluate the characteristics of the generated DMPSM sequences. Unlike optical soliton molecules in mode-locked lasers, the formation of DMPSMs arises from the combined action of multiple timescale coupling, nonlinear bistability, and time-delayed feedback in the OEO cavity, where the soliton interval and number in a DMPSM can be well-controlled through varying the multiple timescale variables in the OEO cavity, and the repetition frequency of the DMPSMs can be tuned through changing that of the initially injected perturbation signal. Meanwhile, the generated DMPSM sequence performs with high stability and excellent coherence, which shows enormous application potentials in pulse radar detection, dense microwave comb generation, and neuromorphology.

Versatile, fast, and accurate frequency excursions with a semiconductor laser

Achieving accurate arbitrary frequency excursions with a laser can be quite a technical challenge, especially when steep slopes (GHz/µs) are required, due to both deterministic and stochastic frequency fluctuations. In this work we present a multistage correction combining four techniques: pre-distorsion of the laser modulation, iterative correction, opto-electronic feedback loop, and feed-forward correction. This combination allows us not only to compensate for the non-instantaneous response of the laser to an input modulation but also to correct in real time the stochastic frequency fluctuations. We implement this multistage architecture on a commercial DBR laser and verify its efficiency, first, with monochromatic operation, and second, with highly demanding frequency excursions. We demonstrate that our multistage correction not only enables a strong reduction of the laser linewidth but also allows steep frequency excursions with a relative RMS frequency error well below 1% and a laser spectral purity consistently better than 100 kHz, even in the midst of gigahertz-scale frequency excursions.

Various nonlinear transitions of a self-assembled quantum dot (SA-QD) semiconductor laser subject to negative optoelectronic feedback

Various nonlinear transitions of a self-assembled quantum dot (SA-QD) semiconductor laser subject to negative optoelectronic feedback

Studying the Synchronization for Multiple Transmitter- Receiver Nano Quantum Cascade Lasers.

In this paper, the chaos synchronization of four Nano quantum cascade lasers with optoelectronic feedback was investigated. The present system consists of two receiver lasers and two transmitters lasers. The rate equation model was modulated to study the effect of the Purcell factor F and the spontaneous emission factor because of their importance in a nanocavity. The results indicated that the suggested system, realize the chaos synchronization. Also, the nanocavity parameters F and β, have significant effect on the chaos synchronization quality and may lead to lose it. Furthermore, the results showed the weak effect of delay time on the performance of lasers.

Triple closed-loop resonant micro-optical gyroscope based on optoelectronic hybrid feedback

Triple closed-loop resonant micro-optical gyroscope based on optoelectronic hybrid feedback

Real-time (re)shaping of cardiac action potentials by an opto-electronic feedback control system in the multicellular setting

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Research Council Starting Grant and Consolidator Grant to Daniël A Pijnappels Background The membrane potential (Vm) in cardiomyocytes fulfills essential regulatory roles in various biological functions, including not only action potential (AP) propagation and mechanical contraction, but also homeostatic regulation. In-depth studies into these roles have been severely hampered by the lack of research methods allowing full control over Vm, especially in multicellular cardiac preparations. Purpose We aimed to unlock new research possibilities by the development of an experimental system (APqr) capable of full Vm control, including instantaneous modulation of AP morphology on a multicellular levelin the multicellular setting. Methods Monolayers of immortalized human atrial myocytes (hiAMs, n=7) were genetically modified to express the blue light-activatable cation channel Cheriff and the red light-sensitive inward chloride pump Jaws for depolarizing and re- or hyperpolarizing effects, respectively. Real-time Vm readout was obtained by patch clamp electrophysiology. Deviations of Vm from reference values were calculated by a custom closed-coop controller. A 470-nm and a 617-nm LED were modulated by the controller in a Vm deviation-dependent manner, selectively activating Cheriff or Jaws. Electrical disturbances were introduced by application of 4-aminopyridien (4AP, 200 µM) or a preprogrammed blue-light pulse creating abnormal cation influx during the repolarization phase of the hiAM AP. Results Average AP durations at 90% repolarization (APD90) increased by 82.4 ms following 4AP application and by 362.5 ms in the presence of light-induced abnormal cation influx compared to control conditions. APqr reduced these APD90 differences to 1.9 ms and 4.6 ms on average, with Vm deviations less than 2.5 mV in 74.7% and 94.4% of the time, respectively. APqr could also be applied for the enforcement of arbitrary AP shapes. In these experiments, reference Vm values consisted of APs recorded from hiAM monolayers exposed to drugs with APD-prolonging (4AP) or shortening (carbachol) effects. APqr was able to enforce these reference APs on hiAM monolayers with high accuracy, with Vm deviations less than 2.5 mV in 95.8% and 94.4% of the time, respectively. Conclusions APqr preserves AP morphologies in the presence of electrical perturbations of different origin without any prior knowledge of the disturbance and enforces arbitrary AP morphologies with high accuracy in an immediate and self-regulatory manner. Collectively, these results set the stage for the refinement and application of opto-electronic control systems to enable in-depth investigation into the regulatory roles of the membrane potential in health and disease.

Multiplet cascade in a semiconductor laser with optoelectronic feedback

We report experimentally and theoretically a dynamical scenario involving the formation of pulse multiplet structures, i.e., configurations of two, three, and more pulses per round trip, in a semiconductor laser with positive optoelectronic feedback. The delayed feedback loop includes a cascade of two band-limited amplifiers with nonlinear saturation of sigmoid type. The multiplets appear subcritically in the vicinity of the lasing threshold, resembling gain-switched operation, and evolve with the injection current.

Hybrid integrated optical chaos circuits with optoelectronic feedback

A chip-scale chaotic laser system with optoelectronic delayed feedback is proposed and analyzed by numerical simulation. This chip eliminates the need for bulky delay components such as long optical fibers, free propagation and external cavities, relying solely on internal devices and waveguides to achieve feedback delay. This approach simplifies integration, maintaining a compact chip size. According to the results, the chip-scale system exhibits rich dynamics, including periodicity, quasi-periodicity, and chaotic states. Chaos resembling Gaussian white noise is achieved with picosecond-level delay time, highlighting the complexity of chip-scale signals. Furthermore, time delay signature (TDS) concealment is enhanced with a short delay comparable to the inverse bandwidth τ, albeit at a cost of sacrificing chaotic signal complexity. Applying the photonic integrated circuits to practical applications, 1 Gbps back-to-back communication transmission is feasible. Results demonstrate low bit error rates (BERs) for authorizers (<10−6) and high BERs for eavesdroppers (>10−2), ensuring communication confidentiality and chaotic synchronization. Lastly, preliminary experiments validate the feasibility. Our theoretical work has demonstrated the feasibility of hybrid integrated optical chaos circuits with optoelectronic feedback based on photonic wire bonding, which can provide a stable and flexible integrated chaos source.

Performance Evaluation of Chaotic Semiconductor Laser

Abstract: Chaotic semiconductor lasers are produced for applications in long-distance communication and for concealing modulated messages. In the present work, the dynamics of chaotic behavior in semiconductor lasers utilizing optoelectronic feedback have been investigated using the Optisystem software. Different parameters are controlled to get the optimum chaotic laser. An external perturbation is applied to the semiconductor laser output that has two control parameters, which are frequency and amplitude. Modulation is achieved by the variation in perturbation bias injunction currents while the modulation peak current is fixed. The study employs a delayed optoelectronic feedback diode laser to assess the ability to achieve chaotic output from directly frequency-modulated semiconductor lasers. This is done under various GHz modulation conditions while maintaining a fixed bias current. Keywords: Chaos, Semiconductor laser, Optoelectronic feedback, Optical communication.

Nonlinear Dynamic Behavior of Two Distinct Chaotic Systems

The nonlinear dynamics of two chaotic systems, namely the optoelectronic feedback (OEFB) and the Lu-Chen electronic chaotic system, are simulated and implemented in this work using the Berkeley Madonna software. Control parameters and initial conditions have been adjusted to demonstrate transitions from one state to another. Upon modifying certain regulating elements, both systems exhibited excessive sensitivity to initial conditions and displayed dynamic nonlinear behavior. The OEFB system reveals a homoclinic condition with a Shilnikov attractor as the feedback intensity increases. In contrast, the Lu-Chen system exhibits sensitivity to parameters a, b, and c, accompanied by multiscroll behavior, as evidenced by time series, the Fast Fourier Transform (FFT), and attractor analysis. These results offer potential applications, including data encoding, secure communications, and image processing. This research studied the properties of two different chaotic dynamical systems. These two chaotic systems are optoelectronic feedback and Chua systems. The results are analyzed, and it is found that the behavior of the Chua system changes in the time series, which in turn causes the attractor to change. The results showed a significant increase in the Chua system's bandwidth. Studying the different characteristics opens a broad scope for many applications, the most important of which is secure communications.

10 W super-wideband ultra-low-intensity-noise single-frequency fiber laser at 1 µm.

A 10 W super-wideband ultra-low-intensity-noise single-frequency fiber laser (SFFL) at 1 µm is experimentally demonstrated, based on dual gain saturation effects from semiconductors and optical fibers, together with an analog-digital hybrid optoelectronic feedback loop. Three intensity-noise-inhibited units synergistically work, which actualizes a connection of effective bandwidth and enhancement of noise-suppressing amplitude. With the cascade action of the semiconductor optical amplifier and optical fiber amplifier, the laser power is remarkably boosted. Eventually, an SFFL with an output power of 10.8 W and a relative intensity noise (RIN) below -150 dB/Hz at the frequency range over 1 Hz is realized. More meaningfully, within the total frequency range of 10 Hz to 10 GHz exceeding 29 octaves, the RIN is controlled to below -160 dB/Hz, approaching the shot-noise limit (SNL) level. To the best of our knowledge, this is the lowest RIN result of SFFL within such an extensive frequency range, and this is the highest output power of the near-SNL super-wideband SFFL. Furthermore, a linewidth of less than 0.8 kHz, a long-term stable polarization extinction ratio of 20 dB, and an optical signal-to-noise ratio of over 60 dB are obtained simultaneously. This start-of-the-art SFFL has provided a systematic solution for high-power and low-noise light sources, which is competitive for sophisticated applications, such as free-space laser communication, space-based gravitational wave detection, and super-long-distance space coherent velocity measurement and ranging.

Correlation coefficient of nanolaser based on quantum dot semiconductor laser through optoelectronic feedback an open-loop system

Correlation coefficient of nanolaser based on quantum dot semiconductor laser through optoelectronic feedback an open-loop system

Stabilized Brillouin laser with sub-Hz fundamental linewidth aided by frequency shifted optical injection locking

Stable laser emission with ultra-narrow linewidth plays an important role in making fundamental scientific breakthroughs. Here, we propose and demonstrate a new technique for the generation of an ultra-narrow linewidth and highly stable laser based on stimulated Brillouin scattering in combination with a frequency-shifted optical injection locking mechanism. The laser performance is characterized via a delayed self-heterodyne interference system, where the white frequency noise floor is ∼20 mHz2/Hz, corresponding to a fundamental linewidth of about 63 mHz. The maximum deviation in the output power is less than 1.5% over more than 10 min. The operation of the laser can be stabilized without the need for active optoelectronic feedback. The scheme presented in this work enables narrow linewidth and stable single-frequency fiber lasers in a robust and efficient way, which has shown promising potential for many applications.

Matching points of nanolaser based on quantum dot semiconductor laser for positive and negative optoelectronic feedback strength

Matching points of nanolaser based on quantum dot semiconductor laser for positive and negative optoelectronic feedback strength

Double-Layer Reservoir Computer with Three Nonlinear Nodes Based on Polarization-Multiplexed Optoelectronic Feedback Loops

Double-Layer Reservoir Computer with Three Nonlinear Nodes Based on Polarization-Multiplexed Optoelectronic Feedback Loops

Opto-electronic feedback control of membrane potential for real-time control of action potentials

To unlock new research possibilities by acquiring control of action potential (AP) morphologies in excitable cells, we developed an opto-electronic feedback loop-based system integrating cellular electrophysiology, real-time computing, and optogenetic approaches and applied it to monolayers of heart muscle cells. This allowed accurate restoration and preservation of cardiac AP morphologies in the presence of electrical perturbations of different origin in an unsupervised, self-regulatory manner, without any prior knowledge of the disturbance. Moreover, arbitrary AP waveforms could be enforced onto these cells. Collectively, these results set the stage for the refinement and application of opto-electronic control systems to enable in-depth investigation into the regulatory role of membrane potential in health and disease.

Time-delay signature suppression of the chaotic signal in a semiconductor laser based on optoelectronic hybrid feedback.

An approach to generating chaotic signals with low time-delay signatures (TDSs) from a semiconductor laser (SCL) is proposed and demonstrated based on optoelectronic hybrid feedback. Through using a chirped fiber Bragg grating (CFBG) to provide distributed feedback, a chaotic signal with a low TDS is generated from the SCL. With the assistance of the nonlinear optoelectronic feedback provided by a microwave photonic link, the relaxation oscillation effect in the SCL is effectively suppressed, and the periodicity of the oscillation is greatly weakened. Hence, the TDS of the generated chaotic signal from the SCL is further suppressed, and the effective bandwidth is enlarged. Both simulation and experiment are carried out to verify the feasibility of the proposed scheme to suppress the TDS. In the experiment, a chaotic signal with a large effective bandwidth of 12.93 GHz, an extremely high permutation entropy (PE) of 0.9983, and a low TDS of 0.04, is generated by using a CFBG with a dispersion coefficient of 22.33 ps/nm. This TDS value is at the same level as that obtained by using the SCL-based scheme relying solely on distributed feedback in a CFBG with a dispersion coefficient of 2000 ps/nm.

Collinear acousto-optic filtering of divergent optical beams in the presence of optoelectronic feedback

The divergence of a diffracting light beam affects the characteristics of acousto-optic (AO) interaction. This is due to the side components of the optical beam spatial spectrum propagating in the crystal along the directions different from the beam axis. The divergence causes the AO diffraction efficiency decrease and the distortion of the AO device transmission function — its bandwidth increases and the side lobes are smoothed. We suggest the method to compensate the optical beam effect on the collinear AO diffraction transmission functions shape based on optoelectronic feedback circuit application connecting the AO cell optical output and its piezoelectric transducer. It is shown that such method makes it possible to narrow the transmission function passband and increase the spectral contrast of the system. It is found out that feedback does not affect the AO diffraction transfer functions. Thus, the introduction of feedback makes it possible to increase the spectral resolution of AO devices without compromising the AO device angular aperture.