Visible Molecular Lasers - REU Supplement

这项研究计划是美国国家科学基金会资助的激光物理实验工作的继续，ECS-8411743。其目标是在可见光和紫外光区域开发新的高效可调谐相干辐射源，并更好地了解现有和潜在的新辐射源中发生的基本过程。其中一个实验是为了在可见光下演示光泵浦、连续的HgBr、HgI或PbI激光。HgBr2、HgI2或PbI2的电离解或光学离解之后，将被光学激发(用连续紫外光激光器或弧光灯)从基态激发B态。测量激光器的阈值泵浦功率和研究使用富同位素的金属卤化物盐来提高小信号增益是这项研究的两个主要初始目标。还提出了从最低亚稳态的N_2或CO的激发转移泵浦的准连续氟化碘(IF)激光器的可行性。电子束产生的亚稳分子将与I2和F2混合在圆柱形喷嘴中，并用连续波染料激光检测到增益的存在。微波探测实验将研究激发态碰撞对活性介质能量负载的限制。

This research program is a continuation of experimental work in laser physics supported under NSF grant ECS-8411743. Its goals are the development of new and efficient sources of tunable coherent radiation in the visible and ultraviolet spectral regions, and a better understanding of the fundamental processes occurring in existing and potential new sources. One experiment is designed to demonstrate an optically-pumped, continuous HgBr, HgI or PbI laser in the visible. The electrical or optical dissociation of HgBr2, HgI2 or PbI2 would be followed by optically exciting (with a CW UV laser or an arc lamp) the B state from the ground state. Measuring the threshold pumping power for this laser and investigating the use of isotopically-enriched metal-halide salts to enhance the small-signal gain are two of the primary initial goals of this research. Also proposed are studies to examine the feasibility of a quasi-CW Iodine Fluoride (IF) laser pumped by excitation transfer from the lowest metastable state of N2 or CO. Electron beam-produced metastable molecules would be mixed with I2 and F2 in a cylindrical nozzle arrangement and the presence of gain detected with a CW dye laser. Microwave probing experiments will investigate the limitations posed by excited state collisions on energy loading of the active medium.