Generalized Steady-State Ab Initio Laser Theory and Applications

该奖项支持理论研究和教育，以推进具有复杂介质和多重散射的新型激光系统的理论描述和设计。许多新颖的现代激光系统涉及复杂的谐振腔几何形状，如微腔，光子晶体，甚至基于具有增益的无序散射介质的随机激光器。这些激光器具有广泛的潜在应用，并且使用传统方法进行模拟和理解具有挑战性。 PI开发了一种称为稳态从头计算激光理论的方法，该方法提供了一种易于模拟和设计的方法，以及对其行为的新物理见解。该方法与激光方程的全时相关数值解相一致，计算量小得多。PI将推广他的稳态从头计算激光理论，旨在发展一个统一的框架来描述许多不同的激光系统。PI将扩展理论来描述多跃迁激光器和半导体增益介质，包括增益扩散的影响，和激光器的注入锁定。当某些激光器在空间中非均匀泵浦时，会发现新类型的激光模式;这种行为与相关波动方程中出现的例外点有关，其中两个解合并。这些现象将被广泛研究，以阐明其含义。 激光器中量子效应的第一原理理论将通过结合稳态从头计算激光器理论（它提供了激光器的经典散射矩阵）和输入-输出理论（它描述了散射的量子算符）而获得。量子涨落决定了激光线宽和光子统计，这可以用PI方法在没有自由参数或唯象参数的情况下预测。PI打算将扩展理论变成用于技术目的的应用激光系统设计的计算工具，例如通信，量子信息处理，光谱测定，投影仪，光学相干断层扫描和成像。 将该方法推广到半导体增益介质将导致量子级联和传统半导体激光器模型的改进。目前正在开发一种使用PI开创的方法进行激光设计的开源计算工具，并将在本项目的过程中提供给学术界和工业界的研究人员。非技术性总结该奖项支持理论研究和教育，重点是提高理解和设计新型激光系统的能力，这是跨科学研究的基础工具，也是现代经济的基础技术 激光器是非线性系统，并且还涉及激光器内外的波传播的复杂模式，因此这些设备的理论是相当具有挑战性的。 新材料和材料系统在形成潜在的激光技术方面发挥着重要作用。该奖项支持理论和相关计算算法的发展，以增强对描述当前开发的新型激光系统的方程的定量解，从而为这些系统提供更好，更有效的设计。 该研究的重要潜在应用领域包括通信、量子信息处理、光谱学、生物传感、投影仪、光学相干断层扫描和成像。 该理论的一个副产品是“反激光”的概念，这是一种选择性吸收具有非常特殊性质的光的新型装置。 目前正在开发一种使用PI开创的方法进行激光设计的开源计算工具，并将在该项目过程中提供给学术界和工业界的研究人员。

TECHNICAL SUMMARYThis award supports theoretical research and education to advance the theoretical description and design of novel laser systems with complex media and multiple scattering playing a central role. Many novel modern laser systems involve complex resonator geometries such micro-cavities, photonic crystals and even random lasers based on disordered scattering media with gain. These lasers have a wide range of potential applications and are challenging to simulate and understand using conventional methods. The PI has developed a method, known as steady-state ab initio laser theory, that provides a tractable way to simulate and design as well as new physical insights into their behavior. The method agrees with full time-dependent numerical solutions of the laser equations with much less computational effort.The PI will generalize his steady-state ab initio laser theory with an aim to develop a unified framework for describing many different laser systems. The PI will extend the theory to describe multi-transition lasers and semiconductor gain media, including the effects of gain diffusion, and injection-locking of lasers. New types of lasing modes are found when certain lasers are non-uniformly pumped in space; this behavior is related to the appearance of exceptional points in the relevant wave equations, where two solutions merge. These phenomena will be extensively studied to elucidate their implications. A first principles theory of quantum effects in lasers will be obtained by combining the steady-state ab initio laser theory, which provides the classical scattering matrix of the laser, with input-output theory, which describes the scattered quantum operators. Quantum fluctuations determine the laser linewidth and photon statistics, which can be predicted with no free or phenomenological parameters with the PI's approach. The PI intends the extended theory to become a computational tool for the design of applied laser systems for technological purposes such as communications, quantum information processing, spectrometry, projectors, optical coherence tomography and imaging. The extension of the approach to semiconductor gain media will lead to improvements in the modeling of quantum cascade and conventional semiconductor lasers. An open source computational tool for laser design using the approach pioneered by the PI is being developed and will be made available to researchers in academia and industry in the course of this project.NONTECHNICAL SUMMARYThis award supports theoretical research and education focused on improving the capability to understand and design novel laser systems, which are fundamental tools in research across the sciences, and a basic technology underlying the modern economy. Lasers are non-linear systems and also involve complex patterns of wave propagation within and outside the laser, hence the theory of these devices is quite challenging. New materials and materials systems play an important role in shaping potential laser technologies. This award supports the development of theory and related computational algorithms to enhance to enable quantitative solutions to the equations describing novel laser systems under current development, hence allowing better and more efficient designs for these systems. Important potential applications for the research are in the areas of communications, quantum information processing, spectrometry, biological sensing, projectors, optical coherence tomography and imaging. A spin-off from the theory is the concept of the "anti-laser," a novel device for selectively absorbing light with only very specific properties. An open source computational tool for laser design using the approach pioneered by the PI is being developed and will be made available to researchers in academia and industry in the course of this project.