Erbium-doped Fiber Dual-ring Laser Research Articles

Two chaotic synchronizations in er-doped fiber lasers and their application in two-channel coding secure communications

A dual-ring erbium-doped fiber laser has nonlinear dynamic characteristics based on optical coupling interaction of lasing from the two laser rings and can send chaotic lasing to encode and mask an information to perform secure communication. Two independent groups of single-ring erbium-doped fiber lasers and a dual-ring erbium-doped fiber laser are used to construct two-channel chaos secure communication system while the synchronization’s physical mathematical model is presented by using the “active-passive” chaotic synchronization method, where a dual-ring erbium-doped fiber laser is used as a transmitter and two independent groups of single-ring erbium-doped fiber lasers are used as two receivers. Our numerical simulation shows that these two receivers can synchronize with the transmitter respectively. A two-channel chaotic hidden encoding secure communications with a modulation frequency of 10kHz analog signal and a rate of 20kbit/s digital signal are numerically simulated respectively, which shows to have good decoding quality and strong security. The obtained result shows that the chaotic coding system can be well applied in chaotic two channel secure communications. The research results have an important reference value for optical multi-channel secure communication and network security.

Four-Parameter Shifts Control Chaos and Lead to Physical Behaviour in a Dual-Ring Erbium-Doped Fiber Laser

We study on a four-parameter shift (FPS) chaos-control method to obtain control of a chaotic dual-ring erbium-doped fiber laser and lead to physics behaviours of two laser rings. To control two chaotic laser rings, the pump parameters and gain parameters of dual-ring lasers are modulated simultaneously by four shift digital signals. It is found that controls of the two chaotic laser rings are realized and physics behaviours of two laser rings can be guided by FPS. As a result, chaos is led to two periodic behaviours. And physics movements of dual-ring lasers are guided to period-4, period-5, period-6, period-7, and some high-order-period. The obtained results have a large helpfulness for people’ study of control of dynamics system, control of chaos, optic control science, laser physics, and erbium-doped fiber laser application.

Study of Chaos Control of a Dual-Ring Erbium-Doped Fiber Laser Using Parameter Method

Abstract This paper aims to study single-parameter and dual-parameter chaos control of a dual-ring erbium-doped fiber laser. We present the control model to pressure chaotic behavior of the laser to a periodic state or multi-periodic states by introducing a periodic mutational signal to adjust the losses of dual ring. When the loss of single ring is shifted between two different levels, the laser behaviors can be deduced to two single-period states, while two rings can emit cyclic pulses. We find a control-locking regime and discuss its frequency characteristic of the laser. When another signal is taken to control to perform on the loss, the laser can be deduced to show a period-2 state, a period-3 state, period-4 state and other multi-periodic states. And we find dual-dynamic controlled regimes, in which, one ring of the laser can be produced to show a periodic state while another ring presents a period-3 state. We find also a dual-period regime or a period-4 regime. When both the losses of dual ring are adjusted by shifting between different levels, the laser can produce a period-4, a period-6 and other multi-periodic states. The result indicates that chaos control of a dual-ring erbium-doped fiber laser can be realized using the single-parameter and dual-parameter methods.

Silicon-Micro-Ring Resonator-Based Erbium Fiber Laser With Single-Longitudinal-Mode Oscillation

In this paper, we propose and experimentally illustrate a wavelength-switchable erbium-doped fiber (EDF) dual-ring (DR) laser with stable single-longitudinal-mode (SLM) oscillation. In the experiment, a silicon-micro-ring-resonator (SiMRR) is applied in the proposed DR cavity for tuning different output wavelengths, when the birefringence loss is adjusted correctly. To compress the densely multilongitudinal-mode oscillations, the DR scheme together with a 2-m unpumped EDF-based saturable absorber is acted as the mode filter. The DR also can produce self-injection loop for an SLM operation. The wavelength tunability is between 1532.61 to 1557.98 nm and the measured 3-dB output linewidth is ∼22.5 kHz. Moreover, the output stabilizations of the proposed SiMRR-based EDF DR laser are also analyzed and discussed.

Erbium-doped fiber dual-ring laser with stable single-longitudinal-mode and 55-nm tuning range

In the investigation, we propose and demonstrate a stabilized and wavelength-selectable erbium-doped fiber (EDF) compound-ring laser with single-longitudinal-mode (SLM) oscillation covering both C-band and L-band ranges. Here, the dual-ring-cavity (DRC) scheme with an unpumped EDF-based saturable absorber (SA) is proposed in the EDF laser to guarantee SLM output. The proposed DRC of EDF laser can produce the mode-filter and ultra-narrowband auto-tracking filter effects to suppress the densely multi-longitudinal-mode (MLM) and extend the effective gain of EDF in a wavelength range of 1525.0–1580.0 nm. In addition, the observed output stabilities of power and wavelength in the proposed EDF DRC laser are also experimented and discussed.

Controlling Chaotic Dual-Ring Erbium-Doped Fiber Laser by Modulating or Shifting the Loss

Controlling chaotic dual-ring erbium-doped fiber laser and the produced dynamics are studied by modulating or shifting the laser loss while the control model is presented to pressure behavior of the laser to a periodic state or multi-periodic states by a periodic signal perturbing or shifting the loss. When the loss of one ring of the laser is modulated via a sinusoidal signal, chaotic behaviors of the dual-ring can be pressured in two single-periodic states while two rings emit cyclic pulses. It indicates that chaotic dual-ring erbium-doped fiber laser is effectively controlled. When another sinusoidal signal is taken to perform on the loss, the laser can be educe to present a period-2 or period-3 state. When the loss is shifted between two different levels, the dual-ring can be deduced to a period-4, a period-6 and other multi-periodic state. The results indicate that controlling chaotic dual-ring erbium-doped fiber laser can be realized via the chaos-control method.

Dynamics of an erbium-doped fiber dual-ring laser

We report results of a numerical investigation on two-dimensional parameter-spaces of a set of four autonomous, seven-parameter, first-order ordinary differential equations, which models an erbium-doped fiber dual-ring laser. By using Lyapunov exponents to numerically characterize the dynamics of the model in the parameter-space, we show that it presents typical self-organized periodic structures embedded in a chaotic region.

Simple erbium-doped dual-ring fiber laser configuration for stable and tunable dual-wavelength output

We propose and experimentally investigate a stable and tunable dual-wavelength erbium-doped fiber (EDF) dual-ring laser scheme. Here, two tunable bandpass filters (TBFs) are used inside the dual-ring gain cavity to generate dual-wavelength lasing. And, due to the gain competition of the EDF gain cavity, the mode-spacing (Δλs) of lasing dual-wavelength will be limited at different operating wavelengths. Hence, the minimum and maximum mode-spacing in the proposed EDF laser scheme are 0.75 and 15.35 nm in C-band range. Besides, the output performances of proposed fiber laser have also been studied and analyzed.

双环掺铒光纤激光器混沌耦合反馈相移控制

双环掺铒光纤激光器混沌耦合反馈相移控制

Dual-wavelength S-band erbium-doped fiber double-ring laser

We propose and demonstrate an S-band CW dual-wavelength erbium-doped fiber (EDF) dual-ring laser using a compound-ring filter (CRF) with various coupling losses inside the gain cavity. Employing a ring filter combined within the cavity, the fiber laser can lase a dual wavelength without any filter inside the ring loop. The dual-wavelength output exhibits a good performance having optical side-mode suppression ratios (SMSRs) of 31.6 and 31.8 dB and output powers of −9.6 and −9.3 dBm at 1505.58 and 1506.43 nm, respectively, when the coupling loss is 30% inside the cavity. In addition, the output stabilities of the dual-wavelength laser have also been analyzed.

Study on the method of controlling chaos in an Er-doped fiber dual-ring laser via external optical injection and shifting optical feedback light

Controlling chaos in an erbium-doped fiber dual-ring laser is studied by injecting an external light and shifting the phase of an optical feedback light. First, the parameters of the externally injected optical signal are adjusted to bring the chaotic laser into a single-period state and a multiperiod state, respectively. In addition, the single-mode locking in a single ring of the laser as well as the dual-mode locking in dual ring of the laser are found. Secondly, the method of optical feedback is used to stabilize chaos by controlling the parameters of the optical devices in an external optical path. We show that the optical negative feedback can stabilize the chaotic laser into a single-period state, while the optical positive feedback can stabilize the chaotic laser into another single-period state and a period-doubling state. Lastly, various dynamical states are produced in the laser by shifting the phase of the optical feedback light.

Synchronizing erbium-doped fiber dual-ring lasers by using the method of feedback modulating-parameter

A method of feedback modulating-parameter is presented to synchronize hyperchaotic systems, and is applied to the hyperchaotic erbium-doped fiber dual-ring laser systems. A circuit is designed in the laser synchronization system to avoid phase-vagueness automatically. Numerical simulation shows that two hyperchaotic erbium-doped fiber dual-ring lasers can be identically synchronized, when the feedback intensity is suitably selected.

Synchronization of chaotic erbium-doped fiber dual-ring lasers by using the method of another chaotic system to drive them.

A method of chaotic synchronization is presented in this paper that uses the chaotic output of one system to drive two other identical chaotic systems. The criterion is defined that, when the maximum conditional Lyapunov exponents (MCLE's) of the two systems are negative, the two systems can be synchronized to each other. As a possible application we numerically investigated the synchronization of chaotic erbium-doped fiber dual-ring laser systems. Numerical calculation shows that when driven by another chaotic system, if the two identical systems are in chaos and their MCLE's, are negative, they can go into chaotic synchronization whether or not they were in chaotic states previously. Simultaneously, we find that the states of the two systems vary with that of the driving system. When the driving system is in different periodic states, the two systems can still retain synchronization and go into corresponding different periodic states.

Synchronization of chaotic systems modulated by another chaotic system in an erbium-doped fiber dual-ring laser system

We show that two chaotic systems in erbium-doped fiber dual-ring lasers can be synchronized by using the output of one chaotic system (called the driving system) to modulate the parameters of the two systems. Numerical calculation shows that when the stiffness of modulation is properly adjusted, the two systems can he synchronized. Simultaneously, we find that when the driving system is in various periodic states, the two synchronized systems can go into periodic states.

CONTROLLING CHAOTIC BEHAVIOUR IN ERBIUM-DOPED FIBER DUAL-RING LASER WITH LINEAR TIME-DELAYED FEEDBACK

A method of chaos control with linear time-delayed feedback based on the scheme of linear feedback is presented in this paper. By using the method, we propose a scheme of controlling chaotic behavior in erbium-doped fiber dual-ring laser with one polarized mode. The results of the computer simulation show that controlling the chaos into the stable states could be realized by adjusting the feedback coefficient and delay time.