Ryan Bulharowski1,Carlos Gutierrez1,Wesley Kinney1,Makhin Thitsa1,2
Mercer University1,Laboratory of Information and Decision Systems, MIT2
Ryan Bulharowski1,Carlos Gutierrez1,Wesley Kinney1,Makhin Thitsa1,2
Mercer University1,Laboratory of Information and Decision Systems, MIT2
We aim to develop advanced control strategies to be utilized in modulating and stabilizing the laser output characteristics in optical and photonic devices which face increasingly high demands on precision and level of performance. Especially, when these devices are used in medical applications or when high-energy ultra short pulses are involved, there is virtually no room for error. Open loop control is inept to handle issues arising from unexpected disturbances or when these devices need to perform well in harsh environment, which is the case for many defense applications. Built-in feedback control capabilities in these devices will regulate the desired output characteristics rendering the device reliable and robust. Pulsed 3-micron diode-pumped lasers find vast applications in a variety of fields ranging from medical instrumentation, environmental applications, and material processing to spectroscopy. For 2.6-3-micron emissions, Er: YLF has generated a lot of research interest recently as a laser gain medium due to its adequate radiation life time at key energy levels to support Q-switching. We studied the laser dynamics of Q-switching at 2.8 micron in Er: YLF laser with cascade lasing at 1.6 and 1.7 micron by control theoretic approach. We investigate the effect of pump power on population density at key energy levels as well as the average output power and various parameters of the laser dynamics such as heat generated in the material. We also propose pumping schemes which produce desired output pulse characteristics. Both mathematical analysis of the feedback control strategy and the numerical simulation results will be presented.