Optical Transitions, Energy Transfer and Laser Operation of Electronic and Molecular Defects in Ionic Crystals

计划对碱卤化物中简单和复杂缺陷的振动和电子跃迁、弛豫和能量转移过程进行更广泛的研究。孤立的分子缺陷，由各种红外激光或电子激发技术激发，将在红外振动荧光的光谱和时间域中探索，存在于与多声子或多光子弛豫或分子间振动能量转移过程的弱或强竞争中。分子缺陷与F中心形成配对组态，在F电子激发下可以产生有效的电子振动(E-V)能量传递到分子模式中，从而导致多步振动发射。在主体材料、分子和光学技术的变化下，研究和阐明电子-电子转移过程的动力学和物理机制。这些缺陷对产生振动超荧光和可见光泵浦振动固体激光器的能力将被系统地探索和开发。除了这些振动发射系统外，还将研究新的F聚集体中心的强电子跃迁，目的是开发具有更稳定的连续波和PSEC锁模操作的色心激光器，在更大的近红外调谐范围内。这些激光器的单模工作将用于各种振动和电子缺陷的高分辨率烧孔实验。他们在纯碱-氰化物和混合碱-氰化物的有序/无序转变方面的积极工作将得到扩展，特别是在新的光学问题和技术方面。

An extended study of vibrational and electronic transitions, relaxation and energy-transfer processes of simple and complex defects in alkali halides is planned. Isolated molecular defects, excited with various ir laser or electronic excitation techniques, will be explored in the spectral and temporal domains for ir vibrational fluorescence, existing in weak or strong competition to multi-phonon or multi-roton relaxation or intermolecular vibrational energy transfer processes. Association of molecular defects with F centers form pair- configurations, which under F-electron excitation can produce efficient electron-vibration (E-V) energy transfer into the molecular modes leading to multi-step vibrational emission. Under variation of host materials, molecules and optical techniques the kinetics and physical mechanism of the E-V transfer process will be studied and clarified. The ability of these defect-pairs to produce vibrational superfluorescence and visible-light-pumped vibrational solid state lasers will be systematically explored and developed. Besides these vibrationally emitting systems, strong electronic transitions of new F-aggregate centers will be studied with the aim of developing color center lasers with improved-stability cw as well as psec mode-locked operation over an extended near ir tuning range. Single mode operation of these lasers will be used for high-resolution hole-burning experiments in various vibrational and electronic defects. Their active work on order/disorder transitions of pure and mixed alkali-cyanides will be extended, particularly towards new optical questions and techniques.