共查询到20条相似文献,搜索用时 31 毫秒
1.
High-frequency broad-band signal generation using a semiconductor laser with a chaotic optical injection 总被引:1,自引:0,他引:1
Uchida A. Heil T. Yun Liu Davis P. Aida T. 《Quantum Electronics, IEEE Journal of》2003,39(11):1462-1467
Chaotic signals with a flat power spectrum over 20 GHz have been generated using two commercially available semiconductor lasers coupled in a unidirectional master-slave scheme. The master laser has an external optical feedback that induces optical chaos in the laser output. A part of the chaotic light output from the master laser is injected into the slave laser. We experimentally demonstrated the generation of broad-band signals up to 22 GHz using lasers whose relaxation oscillation frequency in the free-running state is only around 6.4 GHz. We also show that the experimental results can be well reproduced by numerical simulations using two coupled rate equations. The numerical investigation shows that the high-frequency broad-band signal generation is owing to two key effects: high-frequency oscillations as a result of beating between the master and slave laser lights, and spectrum flattening due to the injection of the chaotic signal. The flatness, stability, and tunability of the power spectra demonstrated in our experiments suggests that the proposed system can be potentially useful for generation of high-frequency broad-band random signals. 相似文献
2.
《Quantum Electronics, IEEE Journal of》2010,46(3):279-284
3.
We theoretically studied synchronization of chaotic oscillation in semiconductor lasers with chaotic light injection. Feedback-induced chaotic light generated from a master semiconductor laser was injected into a solitary slave semiconductor laser. The slave laser subsequently exhibited synchronized chaotic output for a wide parameter range with strong injection and frequency detuning within the injection-locking regime. Our numerical simulation revealed that the synchronized slave laser exhibits remarkable phase locking, even for chaotic light injection. Consequently, synchronization in phase fluctuations becomes dominant over intensity fluctuations. We found that there exists a parameter range where the slave can synchronize in phase only, with no intensity synchronization. However, synchronization can be completely destroyed, both in phase and in intensity, when the phase locking becomes unstable due to four-wave mixing or excited resonance oscillation. The phase locking was studied analytically and the correspondence between numerical and analytical results was shown. We also analytically examined chaos synchronization based on a linear stability analysis from the viewpoint of modulation response of injection-locked semiconductor lasers to a chaotic light signal. As a result, we verified that such injection-locking-induced chaos synchronization results from a quasilinear response of the bandwidth-broadened slave laser due to strong optical injection. 相似文献
4.
We propose and demonstrate a scheme for generating synchronized chaotic mode hopping in two wavelength-tunable lasers. Chaotic mode hopping resulting in large hops in wavelength is induced by delayed feedback of an electrical signal proportional to the intensity of the laser output which passes through an optical filter. Mode hopping among up to 11 modes was experimentally observed and optical signals in each wavelength band show a different on-off modulation time series. Analysis of the time series indicates high dimensionality. By using a unidirectional coupling method that injects part of the output of one laser into another, we can synchronize the chaotic mode hopping of two separate lasers and obtain synchronized chaotic on-off modulation patterns in multiple corresponding wavelength bands. The robustness of the synchronization with respect to the parameter mismatch and the effects of the coupling strength are investigated. The chaotic mode hopping dynamics and synchronization are well described with a numerical model that includes the characteristics of the laser tuning and the filter transmission. A multiplexed data transmission scheme using chaotic carriers is proposed and experiments demonstrate that multiple messages can be simultaneously recovered when chaos synchronization is achieved 相似文献
5.
多变量耦合实现双环掺铒光纤激光器混沌同步 总被引:5,自引:1,他引:4
根据双环掺铒光纤激光器的理论模型,提出多变量单向耦合法实现混沌同步,对主从系统模型进行数学推导,研究不同参数条件下双环掺铒光纤激光器的混沌同步,得到实现混沌同步的条件,并在Simulink平台下动态仿真。结果表明,衰减系数不同的两个双环掺铒光纤激光器,主激光器通过定向耦合器驱动从激光器,主从系统可以实现精确混沌同步,且随着反馈强度的增大,实现系统混沌同步的时间越短,反馈强度的取值范围由衰减系数和耦合系数确定;选取不同的系统初值,主从系统可实现混沌同步,系统初值对达到混沌同步时间的影响可忽略不计;在主从系统中引入随机高斯噪声,主从系统仍可实现较好的混沌同步。 相似文献
6.
Modulations imposed on a chaotic optical signal generated by a semiconductor laser can be suppressed by injecting the signal into another similar laser under conditions for chaos synchronization. This filter effect could be used to recover messages hidden in chaotic carriers for robust and secure communications. We use a numerical model to examine the filter properties and show that the filter can be described in terms of differences in characteristic transmission functions for imposed signal and chaotic carrier in the output of the synchronized laser. The filter effect is shown to be larger for lower frequencies and decreases as frequencies approach the relaxation oscillation frequency of the laser in the gigahertz regime, similar to the response of steady-state injection-locked lasers to small-signal modulation. The filter properties are confirmed in experiments using both single and multimode lasers. 相似文献
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基于激光边带注入法在铷原子蒸气中实现了电磁诱导透明、光脉冲的减速和存储.为实现对铷原子的相干操控,将主激光器的输出锁定在铷87原子D1线F=1→F'=2的跃迁谱线上,经6.8 GHz电光调制器(EOM)调制后,负一阶频率边带与D1线F=2→F'=2跃迁频率共振.将负一阶频率边带注入锁定从激光器,主激光器和从激光器输出的两束激光和铷原子的两基态超精细能级达到双光子共振,实现相干操控铷原子.将主激光器和从激光器输出的两束激光作为探测光和耦合光输入到铷泡中,通过操控两光束的波形和开关观察到电磁诱导透明、光脉冲的减速和存储. 相似文献
9.
T. Perez M. Radziunas H.-J. Wunsche C.R. Mirasso F. Henneberger 《Photonics Technology Letters, IEEE》2006,18(20):2135-2137
We present numerical simulations describing the dynamics of two multisection semiconductor lasers emitting in a chaotic regime coupled in a master-slave configuration. By changing the current of the passive section of the master laser, we observe a change in the maximum correlation between the outputs of the two systems. These devices are promising candidates for on-off phase-shift keying encryption. 相似文献
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Synchronization of chaotic external-cavity diode lasers has been studied in a master-slave configuration. A message is encoded into the chaotic master laser by amplitude modulation and transmitted to the slave laser. A scheme for decoding the message at the slave is demonstrated 相似文献
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13.
Characteristics of Fast Physical Random Bit Generation Using Chaotic Semiconductor Lasers 总被引:1,自引:0,他引:1
《Quantum Electronics, IEEE Journal of》2009,45(11):1367-1379
14.
Amplitude-modulation (AM) sideband injection-locking characteristics of 1.3-μm distributed-feedback lasers are studied experimentally. When the master laser light, which is amplitude-modulated, is injected into slave lasers, the slave lasers can be phase-locked to each sideband of the master laser. This means that the frequency separation between slave lasers can be controlled by the modulation frequency of the master laser. By controlling the injection power, it is possible to achieve a very stable AM sideband injection-locked state of slave lasers. Results on phase-noise and phase-modulation measurements, the frequency stabilization between two channels, and the injection locking to a short pulse are presented. On the basis of the experimental results, an example for designing the multifrequency laser transmitter by means of the AM sideband injection-locking and the mode-locking techniques is described 相似文献
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16.
Ke Shen Rong Wang 《Quantum Electronics, IEEE Journal of》2001,37(8):960-963
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 相似文献
17.
Pao-Lo Liu 《Lightwave Technology, Journal of》1985,3(1):205-208
Small side modes which contain on the average only a few percent of the total output of injection lasers can cause high bit-error rates through power fluctuations. By measuring the RF spectrum and the bandwidth dependence of the statistical power distributions, we have clarified the nature of these fluctuations. We find that although a laser is driven above threshold, an individual small side mode behaves like a chaotic light source, i.e., a laser biased below threshold. 相似文献
18.
Injection locking and synchronization of periodic and chaotic signals in semiconductor lasers 总被引:6,自引:0,他引:6
Yun Liu Davis P. Takiguchi Y. Aida T. Saito S. Jia-Ming Liu 《Quantum Electronics, IEEE Journal of》2003,39(2):269-278
We experimentally investigate the synchronous response of a semiconductor laser to the injection of a periodic or chaotic oscillating optical signal that is generated by a similar semiconductor laser with optical feedback. We show that there are two different types of synchronous response, appearing in separate regimes of laser frequency detuning and injection strength. They are distinguished by the time lag of the slave-laser response with respect to the injection signal from the output of the master laser. The experimental observations are well described by a numerical model consisting of a set of rate equations. It is revealed that the first type of synchronous response corresponds to the complete synchronization solution of the equations and the second type of response is the result of strong driving. The relevance of these two types of synchronous behavior to a number of recent experiments on chaos synchronization and their implications for data encoding/recovery using chaotic carriers are discussed. 相似文献
19.
Sungchul Kim Byoungho Lee Dong Hwan Kim 《Photonics Technology Letters, IEEE》2001,13(4):290-292
Chaos synchronization in two separate erbium-doped fiber lasers through a 1.5-km-long fiber is experimentally demonstrated. Two identical erbium-doped fiber lasers are fabricated and modulated by an optical modulator near the relaxation oscillation frequency of the fiber laser. At this frequency, the two fiber lasers generate chaotic carriers. When the synchronization conditions such as cavity length, modulation frequency, and laser characteristics are satisfied, the two chaotic fiber lasers are synchronized 相似文献
20.
Cotteverte J.-C. Ropars G. Le Floch A. Bretenaker F. 《Quantum Electronics, IEEE Journal of》1994,30(11):2516-2525
The vectorial injection locking of a slave laser by a linearly polarized master laser is theoretically and experimentally investigated, taking the nature and the stability of the eigenstates of the slave laser into account. It is proved that the behavior of the polarization, intensity, and frequency of the slave laser can be described by four nonlinear coupled differential equations, for lasers in which population inversion remains quite constant. In particular, it is shown that the stability of the eigenstates of the slave laser plays a dramatic role in the response of this laser to injection. Isotropic slave lasers are shown to follow adiabatically the polarization of the master laser in the frequency locking range. Loss anisotropic slave lasers exhibit a specific Adler tongue behavior and can support the transfer of the polarization of the master laser only along their eigenstates. Phase anisotropic slave lasers are shown to exhibit two bistable or simultaneous Adler curves and to offer new possibilities of all-optical command. In all of these cases, a good agreement is obtained between theory and experiment and the study of polarization throws light on the physics of injection locking 相似文献