共查询到19条相似文献,搜索用时 187 毫秒
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提出双环掺铒光纤激光器耦合反馈控制混沌的物理模型,利用定向耦合器将系统的输出变量反馈到系统中,通过间接控制损耗系数,并选取适当的反馈系数,实现对系统混沌的控制。分析了反馈系数对激光器由混沌态进入周期态和稳定态的动力学行为的影响。数值模拟表明:改变系统损耗系数,双环掺铒光纤激光器可由周期态进入混沌态;加入耦合反馈,适当调制反馈系数,可以将双环光纤激光器混沌控制到周期态和稳定态上;提高系统反馈系数,系统进入稳定态的时间变短。选取不同的系统初值,激光器总能得到两种不同的奇怪吸引子,可见双环掺铒光纤激光器具有双稳态特征。 相似文献
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双环掺铒光纤激光器混沌控制产生周期脉冲及多周期现象研究 总被引:3,自引:1,他引:2
研究了双环掺铒光纤激光器混沌控制产生周期脉冲以及多周期现象,并提出了光调制器调制泵浦控制、外部光注入控制、光衰减器控制、光延时时间控制器控制以及相位控制器控制和连续键控反馈光等多种双环掺铒光纤激光器的混沌控制方法.结果表明:用光调制器调制泵浦光能控制激光到周期态及多周期态;用外部光注入能控制激光到单周期态、双周期态、三周期态、四周期态、五周期态以及多种高周期态等,能形成多种形式相空间图样,产生双环掺铒光纤激光器独特的激光单锁模拟和双锁模拟现象;用外部光路反馈控制时,在负反馈条件下,用时间控制器控制反馈光的延时时间能控制激光到不同的周期态和双周期态,用光衰减器控制光的强度能控制激光到稳定态及周期态,用相位调制器控制反馈光的相位进行负反馈和正反馈转换时能有效地控制激光进入到稳定态及周期态;连续键控反馈光相位能控制激光到多周期态等.整个控制系统能动态、有效地控制产生周期光脉冲以及多种新颖的多周期态等. 相似文献
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基于单模双环掺铒光纤激光器混沌反馈相移控制方法和物理模型,分别对两种单环反馈相移的物理模型作了讨论。利用耦合器将系统的输出量反馈到系统中,选取适当的反馈系数,并在反馈通道上加入相移控制器控制反馈光的相移,通过对反馈系数和反馈光相移的控制可以有效地控制激光输出的混沌态、稳定态和周期态。在此基础上,对激光器双环反馈相移控制方法作了详细分析,研究了反馈系数和反馈相移对单模双环掺铒光纤激光器激光混沌双环反馈相移控制模型的影响,并得到一定的规律。 相似文献
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提出双环单模掺铒光纤激光器激光混沌耦合反馈相移控制方法和物理模型,利用耦合器将系统的输出量反馈到系统中,选取适当的反馈系数,并在反馈通道上加入相移控制器PC控制反馈光的相移,通过对反馈系数和反馈光相移的控制,实时、动态、有效地控制激光混沌到稳定态和周期态;分析了系统输出状态随着控制参数变化的演化规律,控制参数的变化可以使得系统的输出产生丰富的有一定规律性的激光动力学现象;讨论了混沌被控制到单周期态时系统输出的振荡周期的变化规律与控制量的关系。 相似文献
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在实验中观察到了掺铒光纤激光器中自脉冲,并通过加反馈的方法控制了自脉冲。在理论上利用带反馈的两激光器的耦合模型,成功地解释了自脉冲的产生及其控制的物理机制。结果表明,掺铒光纤激光器中两正交偏振态的反馈及其耦合对光脉冲的形成及控制的重要性。 相似文献
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The resistively--capacitively--inductively-shunted (RCL-shunted)
Josephson junction (RCLSJJ) shows chaotic behaviour under some
parameter conditions. Here a scheme for controlling chaos in the
RCLSJJ is presented based on the linear feedback theory. Numerical
simulations show that this scheme can be effectively used to control
chaotic states in this junction into stable periodic states.
Moreover, the different stable period states with different period
numbers can be obtained by appropriately adjusting the feedback
intensity and delay time without any pre-knowledge of this system
required. 相似文献
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The resistively-capacitively-inductively-shunted (RCL-shunted) Josephson junction (RCLSJJ) shows chaotic behaviour under some parameter conditions. Here a scheme for controlling chaos in the RCLSJJ is presented based on the linear feedback theory. Numerical simulations show that this scheme can be effectively used to control chaotic states in this junction into stable periodic states. Moreover, the different stable period states with different period numbers can be obtained by appropriately adjusting the feedback intensity and delay time without any pre-knowledge of this system required. 相似文献
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提出外腔延时反馈半导体激光器混沌偏振可调控制方法,分别建立了垂直正交偏振延时双反馈、同偏振面方向延时双反馈以及任意可调偏振延时双反馈激光动力学物理模型. 通过调节激光器外腔光路中的平面镜和光衰减器可控制一平面偏振反馈光的延时时间及光反馈量,或调节一偏振反馈光的偏振面到另一个偏振反馈光的偏振面方向上或者到任意偏振方向都可进行激光混沌控制. 数值结果证明该方法可以控制激光混沌到单周期态、多周期态等,还发现该控制可使激光器同时呈现偏振周期振荡、偏振反周期振荡、稳定三种动力学行为等.
关键词:
混沌
控制
激光器
偏振 相似文献
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The chaotic behaviours in the p--Ge photoconductor system
are studied by changing the photo-excitation coefficient and the
routes and parameter conditions are given for chaos generation in
this system. A scheme for controlling chaos in the p--Ge
photoconductor is presented by adding an ac bias current. Numerical
simulations show that this scheme can be effectively used to control
chaotic states into stable period states for this system. Moreover,
the different period states with different period numbers can be
obtained by appropriately adjusting the amplitude, frequency, and
initial phase of the additional ac current. 相似文献
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We present a scheme for the anti-control of chaos in the p--Ge
photoconductor system by using a chaotic laser to irradiate and
disturb this system. The numerical simulations show that this scheme
can be effectively used to control periodic states in this p--Ge
system into chaotic states. Moreover, the different chaos states
with different chaotic orbits can be obtained by appropriately
adjusting the disturbance intensity and disturbance frequency, and
by increasing this intensity or reducing this frequency, this p--Ge
system gradually evolves to fully developed chaotic states. 相似文献
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We consider the nonlinear dynamics of multiwavelength laser cavities with saturable transmitter and saturating homogeneous gain using a simple and general discrete model. Saturable transmitter is an intensity dependent loss in which the transmittance decreases when the incident optical power increases. We determine the condition under which the saturable transmitter will generate behaviors such as stable steady-state lasing states, periodic lasing states, and chaotic lasing states. Indeed, for sufficiently large power, steady-state operation is first destabilized through a Hopf bifurcation which generates periodic lasing solutions. This is followed by a sequence of period doubling bifurcations to chaotic lasing. The bifurcation structure leading to chaos is characterized by three key methods of dynamical systems: a Feigenbaum series, the calculation of Lyapunov exponents and the computation of the correlation dimension of the system. We found that even single wavelength operation can exhibit complex nonlinear dynamics if the loss element is a saturable transmitter. 相似文献
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The spatial structure of a Bose-Einstein condensate (BEC) loaded
into an optical lattice potential is investigated and the spatially
chaotic distributions of the condensates are revealed. A method of
chaos control with linear feedback is presented in this paper. By using the method, we propose a scheme of controlling chaotic behavior in a BEC with atomic mirrors. The results of the computer simulation show that controlling the chaos into the stable states could be realized by adjusting the coefficient of feedback only if
the maximum Lyapunov exponent of the system is negative. 相似文献
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Hyperchaotic behaviours and controlling hyperchaos in an array of RCL-shunted Josephson junctions 下载免费PDF全文
This paper deals with dynamical behaviours in an array composed of two resistive-capacitive-inductive-shunted (RCL-shunted) Josephson junctions (RCLSJJs) and a shunted resistor. Numerical simulations show that periodic, chaotic and hyperchaotic states can coexist in this array. Moreover, a scheme for controlling hyperchaos in this array is presented by adjusting the external bias current. Numerical results confirm that this scheme can be effectively used to control hyperchaotic states in this array into stable periodic states, and different stable periodic states with different period numbers can be obtained by appropriately choosing the intensity of the external bias current. 相似文献
19.
《Physics letters. A》2002,295(4):220-225
We investigate transitions between the chaotic and regular states through a perturbed chaotic solution of a rf-driven Josephson system. It is shown that the transition from order to chaos may occur when the system initially near the heteroclinic points. The chaotic solution tends to an unstable periodic one for the initial values sufficiently nearing the heteroclinic orbit but going beyond the heteroclinic points. Thus the Josephson chaos can be analytically and numerically controlled, by adjusting the initial conditions. 相似文献