Ultrashort Pulse Propagation and Amplification in New Cr-Doped LiSAF and LiCAF Solid State Laser Materials

由于激光材料cr掺杂LiSAF和cr掺杂LiCAF的发展，在强、超短激光脉冲技术及其应用领域开辟了一条新的机遇之路。与其他尚未开发的材料不同，这些材料显示了产生超强、超短激光脉冲所需的固态激光材料的最具吸引力的特性。它们具有高增益和能量存储性能，良好的光学性能，高损伤阈值，可以大尺寸生长。此外，它们独特地结合了长荧光寿命（LiSAF为70 us， LiCAF为130 us）和已知最宽的光谱发射带（LiSAF为220nm），首次实现了闪光灯泵浦的超短（100fs）大直径脉冲的高增益放大。固态激光模块。这对未来超短、高强度激光技术的应用、实验室x射线激光器的发展、亚皮秒x射线研究和粒子加速具有重要意义。我们将对这两种材料的所有物理性质及其作为超短激光脉冲高增益放大器的应用进行全面的研究。这将包括对cr掺杂LiSAF和LiCAF的基本光谱和原子特性的全面检查，这些特性与宽带脉冲放大有关，它们放大短脉冲的能力，啁啾脉冲放大（CPA）提取能量的有效性，以及影响其在大孔径多分段阵列（MSA）放大器中使用的材料特性。因此，这项研究将解决将这些新材料作为主要激光放大介质所必需的所有问题。有了这项研究产生的数据，我们将能够在未来的工作中，朝着能够在小于100fs的时间内发射数十甚至数百焦耳的激光器的建设迈进，可聚焦到大于1020W/cm2的强度。

A new avenue of opportunity in the field of intense, ultrashort laser pulse technology and its applications has opened as a result of the development of the laser materials Cr-doped LiSAF and Cr-doped LiCAF. These materials, like no others yet developed, display the most attractive characteristics of a solid state laser material required for the generation of ultra-intense, ultrashort laser pulses. They have high gain and energy storage properties, good optical properties, a high damage threshold and can be grown in large sizes. Moreover, they uniquely combine long fluorescence lifetimes ( 70 us for LiSAF and 130 us for LiCAF) and the broadest spectral emission bandwith known (220nm for LiSAF), making possible, for the first time, the amplification with high gain, of ultrashort ( 100fs) pulses with flashlamp-pumped, large diameter, solid state laser modules. The implications will be considerable for future applications of ultrashort, high intensity laser technology, in the development of laboratory x-ray lasers, sub-picosecond x-ray studies, and particle acceleration. We will make a comprehensive investigation of all the physical properties of these two materials associated with their use as high gain amplifiers of ultrashort laser pulses. This will include a full examination of the basic spectral and atomic properties of Cr-doped LiSAF and LiCAF pertaining to broadband pulse amplification, their capacity to amplify short pulses, the effectiveness with which chirped pulse amplification (CPA) can extract energy, and those material properties affecting their use in wide aperture, multi-segmented array (MSA) amplifiers. This study will therefore address all the issues necessary to incorporate these new materials as a major laser amplifier medium. Armed with data produced by this study, we will then be able, in future work, to move forward towards the construction of lasers capable of emitting tens, perhaps hundreds of joules in times of less than 100fs, focusable to intensities greater than 1020W/cm2.