I. The mode locked dye laser. II. Picosecond photoconductivity of semi-insulating gallium arsenide

The first part of this thesis deals with the principles and practice of the passive mode locking of a CW dye laser. This discussion includes the dynamics of picosecond pulse production as well as the techniques of high resolution pulse width measurement. The characterization of the mode locked dye laser through real-time temporal and spectral measurements is also described. The second part of the thesis describes the development and applications of the opto-electronic semiconductor switch. Design considerations of the high speed photoconductive device and results of experiments in which picosecond pulses activate the devices are discussed. The experimental results are interpreted to yield numerical estimates of carrier recombination rates. A new experimental technique of determining these parameters through ultrafast magnetophotoconductivity is introduced as well. The results of this technique show good agreement with the steady state measurements