Research On Novel Fiber-Semiconductor Hybrid Cavity Tunable Lasers

With the development of optical communication, the capacity and rate of the data transmission are increasing stably. The tenability, accuracy and stability of light sources are essential for modern optical fiber communication systems. In this thesis, a kind of novel fiber-semiconductor hybrid cavity (FSHG) tunable laser is studied. The FSHC tunable lasers can provide tunable single-frequency output laser with narrow line-width. The laseing wavelength can be broadly tuned by simply changing the states of the filter within the cavity. This kind of devices can find potential application in high-speed optical communication systems and WDM optical networks.In this thesis, on the foundation of theory analysis on the Fabry-Perot semiconductor lasers, the one-dimensional theoretical model was established and the working characteristics of the FSHC tunable lasers were analyzed systematically in the time domain and spectrum domain respectively via numerical simulation. Including the following aspects:1. From the basic theory of lasers, the theoretical model and operating principles of FPLDs are described. The carrier rate equation and a set of optical-field traveling-wave equations (have been derived based on) are derived from a random expanding of the optical field within the cavity of devices. The analytical expression and the results of the material gain and the spontaneous emission are given.2. The basic design principles, components and operating principles of FSHC tunable laser are described in detailed.3. The one-dimensional traveling-wave rate equations of FSHC lasers are studied employing a split-step time-domain dynamic modeling (SS-TDM) for the numerical implementation with FORTRAN. The dynamic working characteristics of FSHC lasers are analyzed in detail. The results include aspects of the carrier density along the length of cavity and time, the output power variation with time, and power spectrum of the lasers.4. The analysis on the characteristics of output spectrum is difficult, hence the spectrum domain characteristics of FSHC lasers are analyzed and discussed in detail employing the extend transfer matrix method, based on the carrier density distribution obtained from the time domain analysis. The spectrum and the threshold gain of FSHC lasers are analyzed. The tunable characteristics of the output spectrum of FSHC lasers are also studied and analyzed in this paper. Meanwhile, the affect of various parameters on the properties of the devices are simulated.