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外腔延时特征和带宽是影响混沌激光应用的两个重要参量.本文将一个单路光反馈的半导体激光器输出的激光部分地注入到另一个双路滤波光反馈的半导体激光器中,从而构成一个具有外光注入的双路滤波光反馈半导体激光器系统,即主从激光器系统,用于抑制混沌激光的延时特征并研究其带宽.数值研究了外光注入系数、反馈强度、抽运因子和滤波器带宽对系统输出混沌激光的延时特征的影响,然后将该系统对延时特征的抑制效果和具有外光注入的单路光反馈半导体激光器系统、具有外光注入的双路光反馈半导体激光器系统、具有外光注入的单路滤波光反馈半导体激光器系统以及无光注入双路滤波光反馈半导体激光器系统进行对比和分析,结果表明本文提出的方案对延时特征的抑制效果最好.然后在本文提出的具有外光注入的双路滤波光反馈半导体激光器系统中,延时特征被有效抑制的参数条件下研究系统输出混沌激光的带宽,结果表明,通过适当选择参数的取值,本文提出的方案可以提高系统输出混沌激光的带宽. 相似文献
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Viktorov EA Mandel P O'Driscoll I Carroll O Huyet G Houlihan J Tanguy Y 《Optics letters》2006,31(15):2302-2304
We study the feedback-induced instabilities in a quantum dot semiconductor laser emitting in both ground and excited states. Without optical feedback the device exhibits dynamics corresponding to antiphase fluctuations between ground and excited states, while the total output power remains constant. The introduction of feedback leads to power dropouts in the ground state and intensity bursts in the excited state, resulting in a practically constant total output power. 相似文献
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The dynamic characteristics of a semiconductor laser with optical feedback are strongly dependent on the injection current and the reflectivity and position of the external feedback reflector. We investigated the relaxation oscillation enhancement and coherence collapse state of the laser oscillation based on the laser rate equations. It is well known that laser output power jumps with increase of the injection current due to external mode transition. But here for the first we time demonstrate the existence of a chaotic scenario within successive laser power jumps. The results calculated by numerical simulations based on the rate equations are compared with those of the experiments and good coincidence between them is found. 相似文献
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本文在理论上研究了由于外部光反馈引起的半导体激光器的相位噪声.理论分析是通过引入一个反馈耦合率K和线性化速率方程,导出了半导体激光器相位噪声功率谱密度的表达式.这表明相位噪声功率谱密度随外腔长度而周期性地漂移,且功率谱密度的峰值随外部反馈耦合率而发生很大的变化. 相似文献
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We propose a power spectrum analysis method to directly identify the time delay of a chaotic semiconductorlaser with optical feedback. By measuring the radio frequency (RF) power spectrum of the chaotic laserand performing an inverse Fourier transform, we can easily unveil all the time delay signatures, regardless ofwhether the chaotic output is induced by single or multiple feedback. This method successfully retrieves thetwo time delay signatures from the power spectrum of a semiconductor laser with double-cavity feedback. 相似文献
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通过增加外腔反馈式半导体激光器的激光反馈时间,使系统处于混沌状态,再采用滑模变结构控制方法实现这种激光器的混沌控制.该方法的优点是系统既能很快地获得稳定的输出激光,又能根据工程需要实现激光输出功率强度的灵活调整.理论分析和数值计算结果表明控制结果具有很强的稳定性和鲁棒性.研究结果对改善实际激光系统稳态输出的快速性、输出功率的灵活可调性和能量转换效率有较好的参考价值.
关键词:
混沌
外腔反馈式半导体激光器
滑模变结构控制
外腔长度 相似文献
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Chaotic dynamics of a semiconductor laser subject to incoherent optical feedback (IOF) are experimentally investigated, and the external cavity time are retrieved and measured from intensity time series of the laser output by using self-correlation function and the mutual information. Through moderating feedback strength and injection current of the laser, the external cavity time signature of the laser chaotic output is effectively attenuated, and then the security of such chaos encryption system can be assured to a certain degree. 相似文献
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The stability enhancement of laser output power for the change of external cavity position in semiconductor lasers with optical feedback is observed by experiment. The relaxation oscillation frequency which plays an important role in the dynamics of the nonlinear system is also investigated as a function of the external cavity length. The period of the stability enhancement along the position of the external cavity is exactly coincident with the length corresponding to the relaxation oscillation frequency of the solitary laser. The experimental results are compared with theoretical and excellent coincidence between the two is found. 相似文献
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A smart scheme for chaotic signal generation in a semiconductor ring laser (SRL) with optical feedback is proposed and investigated numerically. The chaotic oscillation in the SRL can be generated by the partial reflection of the laser output. Time series, attracter and the power spectrum, as well as the Lyapunov exponent spectrum, are calculated and analyzed. We also study the synchronization scheme of feedback-induced chaos in SRLs by optical injection that consists of a drive SRL with optical feedback and a response SRL with optical injection from the drive laser. High-quality synchronization is achieved with suitable injection strength and detuning frequency between the drive and the response SRLs. 相似文献
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A. Bakry S. Abdulrhmann M. Ahmed 《Journal of Experimental and Theoretical Physics》2016,122(6):960-969
We theoretically model the dynamics of semiconductor lasers subject to the double-reflector feedback. The proposed model is a new modification of the time-delay rate equations of semiconductor lasers under the optical feedback to account for this type of the double-reflector feedback. We examine the influence of adding the second reflector to dynamical states induced by the single-reflector feedback: periodic oscillations, period doubling, and chaos. Regimes of both short and long external cavities are considered. The present analyses are done using the bifurcation diagram, temporal trajectory, phase portrait, and fast Fourier transform of the laser intensity. We show that adding the second reflector attracts the periodic and perioddoubling oscillations, and chaos induced by the first reflector to a route-to-continuous-wave operation. During this operation, the periodic-oscillation frequency increases with strengthening the optical feedback. We show that the chaos induced by the double-reflector feedback is more irregular than that induced by the single-reflector feedback. The power spectrum of this chaos state does not reflect information on the geometry of the optical system, which then has potential for use in chaotic (secure) optical data encryption. 相似文献
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L. Cardoza-Avendaño R.M. López-Gutiérrez C. Cruz-Hernández 《Optics & Laser Technology》2011,43(5):949-955
We have experimentally investigated chaotic power oscillations in single-longitudinal mode DFB and multi-longitudinal mode FP lasers as a function of incoherent optical feedback strengths of up to 42%. We have demonstrated the existence of chaos in the output oscillations of both laser types using classical experimental tools such as RF spectrum, standard deviation, and maximum Lyapunov exponent, which all increase with increasing of feedback strength for both in single-longitudinal mode DFB lasers and multi-longitudinal mode FP lasers. It is also shown that power switching among longitudinal modes of multimode FP semiconductor laser is a considerable portion of the chaotic power oscillations for both strong and weak incoherent optical feedback. 相似文献
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In this paper, the dynamical response of a slave semiconductor laser, with short cavity, under injection of a chaotic light from a master semiconductor laser has been widely studied. This is analyzed numerically via bifurcation diagrams, in terms of the phase and strength of the feedback, as control parameters. It is shown that, both of these parameters should be considered in the dynamical response of the slave laser. Our numerical calculations show that the dynamics of the slave laser imitates the master laser, in addition to the feedback strength, it also heavily depends on the injection dynamics and rates. Numerical results also show that for different values of the control parameters, the intensity of the slave laser output can be fully different from the injection source. However, we found out under appropriate conditions, that the dynamics of the slave can be the same as the master laser. The results also show that the output of the slave laser, compared to its output without injection, can be stabled in the appropriate values of the injection rate from the master laser. 相似文献
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A practical scheme for polarization-insensitive and frequency-conversion interval-independent four-wave mixing in an optical loop configuration is proposed that uses one conventional semiconductor optical amplifier device and two perpendicular polarized pump sources. The significant advantages of this technique are simplicity of configuration, efficient conjugate power generation, effective suppression of the signal and one pump wave at the output port, and reduction in noise. 相似文献
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We demonstrate experimentally and numerically that, by spectrally filtering the delayed optical feedback into a semiconductor laser, one can elicit novel dynamics in the frequency of the laser output light on a time scale that is set by the delay time of the feedback. In particular, we show that through a judicious choice of the filter bandwidth, and its frequency relative to that of the laser, one can produce controlled oscillations in the frequency of light from the laser. 相似文献
18.
Narrow bandwidth operation of high-power broad-area diode laser using cascaded phase-conjugate injection locking 总被引:1,自引:0,他引:1
H. Horiuchi T. Shimura T. Omatsu O. Matoba K. Kuroda 《Applied physics. B, Lasers and optics》1999,68(5):1021-1025
A broad-area laser is injection-locked by another broad-area laser that is also injection-locked by a single-mode diode laser.
Two double-phase conjugate mirrors of photorefractive BaTaO3 are used to couple the master laser beams to the first slave laser, and the first slave laser output to the second slave
laser. One of the double-phase conjugate mirrors is built up with the beams from two broad-area lasers. Two slave lasers are
oscillating in single longitudinal mode at 808.5 nm and the spectral width is the same as that of the master laser. Final
single-mode output power from the second slave broad-area laser is 840 mW, which is limited by the power of the injection
beam. This work verifies the possibility of the multi-stage cascaded injection locking of high-power diode lasers with phase-conjugate
injection.
Received: 18 November 1998 / Revised version: 29 January 1999 / Published online: 7 April 1999 相似文献
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T.W. Carr 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,19(2):245-255
We consider the deterministic dynamics of a semiconductor laser with saturable absorber that is subject to delayed optical
feedback. Alone, both the saturable absorber and delayed feedback cause the CW output to become unstable to periodic output
via Hopf bifurcations. We examine the combined effects of these two destabilizing mechanisms to determine new conditions for
the Hopf bifurcations. We also describe the transient as the unstable CW output evolves to the oscillatory state. A main result
is that the presence of a saturable absorber can increase the sensitivity of the laser to delayed feedback.
Received 1st August 2001 and Received in final form 28 November 2001 相似文献
20.
The frequency of relaxation oscillations in the output power of lasers, particularly semiconductor lasers, is an important
parameter which can be used to inform other fundamental laser variables, for comparison with expected theory, and to show
the effect of external influences, such as optical feedback, by a change in value. Thus, precision measurement of the relaxation
frequency is important. Instantaneous frequency measurement algorithms are applied to experimental semiconductor laser relaxation-oscillation
signals to determine whether reliable values can be extracted, for an extended range of injection current, as compared to
direct measurement and fast Fourier transform techniques. Improvement is achieved but, more importantly, the technique clearly
shows when other oscillations, such as those due to packaging, connectorization and power supply, dominate the oscillatory
component of the output power, at low injection currents. The work further supports the finding that only mid-range injection
currents can be used for reliable precision relaxation oscillation frequency measurement. 相似文献