
Professor Birnbaum and his group, which includes two visiting scientists and four graduate students, conduct a broad research program in solid state lasers and solid state spectroscopy. A major interest is the development of diode pumpable solid state lasers over the 2 to 5 µ m wavelengths. Some unique solid state lasers studied in this program were the Er,Nd:YAG, Ho,Nd:YAG, and Er,Nd:YALO. These lasers provide outputs at both 2.8 to 3.0 µ m (Er and Ho) and 1.06 µ m and 1.34 µ m (Nd). Diode pumped characteristics of these lasers are currently under investigation. Several new projects have been initiated. These include the U3+:crystal laser at -2.5 µ m and the Er:crystal laser at 1.5 µ m. In addition, work directed towards the development of new tunable solid-state lasers and other ions favorable prospects for tunable visible infrared outputs.
Nonlinear optical properties of materials are also under investigation in order to obtain Q-switch laser action and harmonic frequency conversion. Expansion of the research effort to include optical parameters of tunable solid state laser is anticipated.