Micro-ring resonators (MRRs) are employed to generate signals used for optical communication applications, where they can be integrated in a single system. These structures are ideal candidates for very large-scale integrated (VLSI) photonic circuits, since they provide a wide range of optical signal processing functions while being ultra-compact. Soliton pulses have sufficient stability for preservation of their shape and velocity. Technological progress in fields such as tunable narrow band laser systems, multiple transmission, and MRR systems constitute a base for the development of new transmission techniques. Controlling the speed of a light signal has many potential applications in fiber optic communication and quantum computing. The slow light effect has many important applications and is a key technology for all optical networks such as optical signal processing. Generation of slow light in MRRs is based on the nonlinear optical fibers. Slow light can be generated within the micro-ring devices, which will be able to be used with the mobile telephone. Therefore, the message can be kept encrypted via quantum cryptography. Thus perfect security in a mobile telephone network is plausible. This research study involves both numerical experiments and theoretical work based on MRRs for secured communication.

The title explain new technique of secured and high capacity optical communication signals generation by using the micro and nano ring resonators. The pulses are known as soliton pulses which are more secured due to having the properties of chaotic and dark soliton signals with ultra short bandwidth. They have high capacity due to the fact that ring resonators are able to generate pulses in the form of solitons in multiples and train form. These pulses generated by ring resonators are suitable in optical communication due to use the compact and integrated rings system, easy to control, flexibility, less loss, application in long distance communication and many other advantages. Using these pulses overcome the problems such as losses during the propagation, long distances, error detection, using many repeaters or amplifiers, undetectable received signals, pulse broadening, overlapping and so on. This book show how to generate soliton pulses using ring resonators in the micro and nano range which can be used in optical communication to improve the transmission technique and quality of received signals in networks such as WiFi and wireless communication.

Micro-ring resonators (MRRs) are employed to generate signals used for optical communication applications, where they can be integrated in a single system. These structures are ideal candidates for very large-scale integrated (VLSI) photonic circuits, since they provide a wide range of optical signal processing functions while being ultra-compact. Soliton pulses have sufficient stability for preservation of their shape and velocity. Technological progress in fields such as tunable narrow band laser systems, multiple transmission, and MRR systems constitute a base for the development of new transmission techniques. Controlling the speed of a light signal has many potential applications in fiber optic communication and quantum computing. The slow light effect has many important applications and is a key technology for all optical networks such as optical signal processing. Generation of slow light in MRRs is based on the nonlinear optical fibers. Slow light can be generated within the micro-ring devices, which will be able to be used with the mobile telephone. Therefore, the message can be kept encrypted via quantum cryptography. Thus perfect security in a mobile telephone network is plausible. This research study involves both numerical experiments and theoretical work based on MRRs for secured communication.

The purpose of this book was to investigate the temperature and input energy dependency of Nd:YAG laser performance pumped by flashlamp. A commercial laser rod Nd:YAG laser crystal was utilized as a gain medium. The laser rod was placed parallel to a linear flashlamp filled by xenon gas at 450 Torr. The Nd:YAG crystal together with the flashlamp was flooded with a coolant comprising of a mixture with 60% ethylene glycol and 40% distilled water, which covers a range of temperature from -30oC to +60oC. Spectroscopic properties of the Nd:YAG rod under pulsed flashlamp pumping was investigated from the output fluorescence spectrum of the flashlamp radiation and the Nd:YAG rod. The linewidth of each fluorescence line was measured for an estimation of an effective emission cross section and saturation intensity. The influence of temperature and input energy on a fluorescence emission cross section of Nd3+:YAG crystal was studied. The cross-section was found to decrease as the temperature and the input energy was increased. The inter-stark emission showed a Lorentzian line shape indicating homogeneous broadening. This was attributed to the thermal broadening mechanism of the emission line. The spectral widths and shifts of the emission lines for the three and four level inter-Stark transitions within the respective intermanifold transitions of 4F3/2 4I9/2 and 4F3/2 4I11/2 were investigated over the range of 0 to 75 J. The emission lines for the 4F3/2 4I9/2 transitions shifted towards a longer wavelength and broadened, while the positions and linewidths for the 4F3/2 4I11/2 transitions remained unchanged with the increase of input energy. Finally, the temperature dependence of quasi-three-level laser transitions for long pulse Nd:YAG laser was also investigated. The laser performances at both 938.5 nm and 946.0 nm were also found to be inversely proportional to temperature, and the slope efficiency was unchanged with temperature. The reduction was due to the mechanism of phonon scattering as well as a broadening effect while the temperature increased.