Experimental Study On Chaotic DFB Laser Diodes Subject To Sliced Amplified Spontaneous Emission

Chaotic signal play an important role in privacy communication, chaotic lidar, high speed code generator and chaotic optical time domain reflection, as its high bandwidth, large amplitude and8-like autocorrelation performence. Chaotic signal can be easily generated by a laser subject to external perturbation. The commonly used way of perturbation are optical feedback, opto-electronic feedback and optical injection. Chaotic signal generated by optical feedback and opto-electronic feedback has weak periodicity, which have adverse impact on its practical application.chaotic signal without periodicity can be generated by optical injection, but it need severe condition in both injection intensity and injection wavelength, especially the polorization state of injection light. This make an obstacle in chaotic signal’s practical applications. Using sliced amplifier spontaneous emission as an external perturbation, distributed feedback semiconductor laser source will preduce chaotic signal has no periodicity and high complexity, allow larger injection parameters.This dissertation focus on the output of distributed semiconductor laser subject to sliced amplifier spontaneous emission injection, especially the chaotic state output, and the character of output. Detail are summarized as follows:1. The development of the chaos and chaotic laser have been induced. Main applications of chaotic laser has been introduced, and main approaches of generating chaotic signal by perturbance have been introduced briefly, providing contrasting basis for comparison different means of perturbance with sliced ASE injection.2. Experimental parameter and experimental result are detailed elaborated. We consisely anlysed the requirements of practical application and drawbacks of the exiting means of generate chaotic signal, elaborating the research goal and the significance. Specific research on the injection parameters of sliced ASE injection is described in this section. We compare the sliced ASE injection with the commonly used optical injection. The result indicates that the sliced ASE injection can make the DFB laser work in chaotic state in a larger parameter range.3. We analyze the characters of chaotic signal genertated by sliced ASE in periodicity, distribution of amplitude and complexity. Our research results show that perterbing the DFB laser by sliced ASE injection is able to generate chaotic signal have no periodicity, more symmetric distrbution and higher complexity.