Spatial beam-output characteristics of semiconductor lasers with optical feedback - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Spatial beam-output characteristics of semiconductor lasers with optical feedback write by Vahid Gregory Taʼeed. This book was released on 1998. Spatial beam-output characteristics of semiconductor lasers with optical feedback available in PDF, EPUB and Kindle.
Lasing Properties of Microcavity Semiconductor Lasers and Spatial Coherence in Gain Profiled Semicnductor Lasers with Optical Feedback
Lasing Properties of Microcavity Semiconductor Lasers and Spatial Coherence in Gain Profiled Semicnductor Lasers with Optical Feedback - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Lasing Properties of Microcavity Semiconductor Lasers and Spatial Coherence in Gain Profiled Semicnductor Lasers with Optical Feedback write by Guan Hong Wu. This book was released on 2004. Lasing Properties of Microcavity Semiconductor Lasers and Spatial Coherence in Gain Profiled Semicnductor Lasers with Optical Feedback available in PDF, EPUB and Kindle. Investigated in this thesis are some methods to control the optical modes of semiconductor lasers with different cavity geometries such as microdisks, microrings, and broad-area lasers with external cavities. The characteristics of lasing spectra from microdisk and microring semiconductor lasers are examined in detail. Microcavity devices are mounted on either glass substrate or the end facet of a multi-mode optical fiber, which is first realised in the mounting technology area of microcavity lasers. Under optical pumping in pulsed or continuous wave condition at room temperature, all sample devices achieved lasing. Lasing modes have been identified to be consistent with Whispering-Gallery modes. Quality factors are estimated to be of the order of 2500. We also observed for the first time that the mode spectral broadening with microring devices under high pulsed pump powers is attributed to the transient red shift of the lasting mode. These work show that optical pumping is an easy and flexible way to study lasing characteristics of semiconductor microcavity lasers. We can control the wavelength and intensity of optical modes in these devices through changing their diameters and varying their geometries. Two mounting configurations expand the optical pumping schemes and application areas with microcavity lasers. Mounting microcavities on the end facet of fiber will find possible applications in the integrated optical circuit, in which microcavity devices can be coupled with optical fiber as filters, add-drop filters, etc. Further work needs to be done on mounting microcavity devices at the end facet of a single-mode fiber due to the wide adoption of this fiber in telecommunication systems. How the optical feedback from an external cavity affects the spatial coherence of optical modes in gain profiled broad area semiconductor lasers consists of another part of the research work in this thesis. This device shows good spatial coherence with increasing output optical field under pulsed operation but has limited operation range with good spatial coherence under CW condition. The optical feedback reduces the threshold current of the gain profiled device by up to 8%. This is a trivial improvement that could lead to higher reflective coatings on the facets of laser diode. Feedback also restores the symmetry of beam profiles and increases the total intensity of the output beam without degrading its spatial coherence. It reduces the effect of any local perturbations in the thermal lens profile. The appearance of interference fringes between the near field profile segments when the feedback mode matches the output mode perfectly is another evidence of the food spatial coherence with this device. Simulations based on the modified Maxwell-Bloch equation verify the above experimental results.
Spatial Dynamics of Semiconductor Lasers
Spatial Dynamics of Semiconductor Lasers - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Spatial Dynamics of Semiconductor Lasers write by John A. Houlihan. This book was released on 2002. Spatial Dynamics of Semiconductor Lasers available in PDF, EPUB and Kindle. The study of semiconductor lasers over the past 40 years has been concerned with both their operating characteristics and their properties as a non-linear optical system. In particular, the transition from stable dynamical operation to a more complex dynamical state, when the number of degrees of freedom of the system is increased, is of great interest from technological as well as fundamental viewpoints. This thesis will examine two examples of this type of extension namely, the increase in the transverse size of the laser cavity and the effect of delayed external incoherent feedback, on the lasers dynamics. In the former case we will study a mechanism for the stabilization of the chaotic output of the laser and in the latter we will identify some instabilities and discuss their properties. Broad area lasers are ubiquitous in modern optical fiber networks, their main application being the pumping of erbium doped fiber amplifiers. They are characterized by their ease of fabrication and subsequent low cost. However, they display complex chaotic spatio-temporal dynamics at high output powers which leads to a loss in the spatial coherence of the laser beam. This loss in spatial coherence limits the applications of these devices and/or constrains the laser to operate at low output powers. We will analyse, both experimentally and theoretically, a simple technique which may be used to stabilize the output of these simple broad area lasers, namely transverse injection profiling. The mechanism for stabilization of these lasers is identified and an alternative implementation is discussed. In the remainder of the thesis, the effect of incoherent delayed feedback on a single transverse mode, multi-longitudinal mode semiconductor laser is experimentally analysed. This experiment is motivated by the large amount of theoretical and experimental work concerning both regular and phase conjugate optical feedback in semiconductor laser devices. In these situations, the dynamical evolution is determined by the coupling between the carriers, the optical intensity and the phase difference between the laser output and delayed field. In the incoherent case, the phase difference may be neglected. In particular, the effect of phase amplitude coupling, which plays a crucial role in the coherent and phase-conjugate feedback situations, may be neglected in the incoherent feedback case. This is because the external cavity system is no longer sensitive to small changes in the solitary laser frequency. However, the system still displays a number of intensity instabilities, similar to the coherent feedback case, whose nature will be discussed.
Characteristics of Semiconductor Lasers with Optical Feedback
Characteristics of Semiconductor Lasers with Optical Feedback - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Characteristics of Semiconductor Lasers with Optical Feedback write by Jann Oluf Binder. This book was released on 1989. Characteristics of Semiconductor Lasers with Optical Feedback available in PDF, EPUB and Kindle.
Unlocking Dynamical Diversity
Unlocking Dynamical Diversity - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Unlocking Dynamical Diversity write by Deborah M. Kane. This book was released on 2005-04-29. Unlocking Dynamical Diversity available in PDF, EPUB and Kindle. &Quot;This resource illustrates the diversity of dynamic laser states and the technological applications thereof, presenting a timely synthesis of current findings, and providing the roadmap for exploiting their future potential.". "Unlocking Dynamical Diversity illustrates all theory using real-world examples gleaned from international cutting-edge research. Such an approach appeals to industry professionals working in semiconductor lasers, laser physics and laser applications and is essential reading for researchers and postgraduates in these fields."--BOOK JACKET.
