Slow Light: New Physical Mechanisms and Advanced Applications

智力上的功绩。这项研究旨在开发控制光脉冲在材料系统中传播速度的改进方法，并开发这些技术的重要技术应用。这些应用之一是开发具有更高光谱灵敏度的干涉仪。简单的理论论证表明，干涉仪的灵敏度可以提高一倍，就像放在干涉仪一臂中的材料的群指数一样大。在另一项研究中，将实施快光技术，以防止高功率激光系统中发生激光损伤。当光脉冲进入群折射率为正但小于1的材料时，脉冲在空间中被拉伸，从而降低了能量密度。这种效应往往会抑制激光损伤的发生。此外，还将研究光束的相干性如何在以极大群速度传输的材料中传输。还将研究一种控制光速的新物理过程。这个过程涉及到强驱动二能级原子的非线性响应。在强激光场的存在下，一个二能级原子的吸收光谱被强烈修改，并被分成三个分量，每一个分量都具有可用于控制光速的性质。增益和吸收特性都存在，导致光速既慢又快，调制带宽高达几GHz。拟议活动的更广泛影响包括：这项工作将由一个由来自不同种族和文化背景的学生和博士后科学家组成的研究小组进行。他们被鼓励合作，并探索他们研究项目的智力基础。此外，拟议工作的主题领域也是公众非常感兴趣的一个领域。将努力向比学术研究社区更广泛的社区传播这一研究计划的结果。通过这种方式，该项目将努力培养公众，特别是代表人数不足的少数群体对科学和工程的兴趣。

Intellectual Merit. This research is aimed at developing improved methods for controlling the velocity with which light pulses propagate through material systems and at developing technologically important applications of these techniques. One of these applications is the development of interferometers with increased spectral sensitivity. Simple theoretical arguments show that the sensitivity of an interferometer can be increased by a factor as large as the group index of a material placed in one arm of the interferometer. In another study, fast-light techniques will be implemented to prevent the occurrence of laser damage in high-power laser systems. When a light pulse enters a material for which the group index is positive but smaller than unity, the pulse becomes stretched in space, and thus the energy density is lowered. This effect tends to suppress the occurrence of laser damage. Furthermore, studies will be performed of how the coherence properties of light beams are transformed on propagation through materials with extreme group velocities. A novel physical process for controlling the velocity of light will also be studied. This process involves the nonlinear response of the strongly driven two-level atom. In the presence of an intense laser field, the absorption spectrum of a two-level atom is strongly modified and is split into three components, each of which has properties that can be used to control the velocity of light. Both gain and absorption features are present, leading to both slow and fast light speeds, with modulation bandwidths as large as several GHz.Broader Impact. The broader impact of the proposed activity includes the following: This work will be conducted by a research group consisting of students and post-doctoral scientists from diverse ethnic and cultural backgrounds. They are encouraged to work collaboratively and to explore the intellectual underpinnings of their research projects. In addition, the subject area of the proposed effort is one of great interest to the general public. Effort will be made at broadcasting the results of this research program to a community broader than the academic research community. In this manner, this project will strive to foster interest in science and engineering within the general public and especially among underrepresented minorities.