Dispersion and Optical Drag Effects in Rotating Semiconductor Ring Lasers

旋转半导体环形激光器中的色散和光学阻力效应

• 批准号: 0524509
• 负责人: Marek Osinski
• 金额: $ 24万
• 依托单位: University of New Mexico
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0524509&HistoricalAwards=false
• 关键词: Dispersion; Optical; Drag; Effects; Rotating

0524509OsinskiNarrative Summary. Application of standard theoretical approach to ring lasers does not give a clear quantitative answer on the magnitude of the Sagnac effect in a medium with substantial dispersion (such as in semiconductor materials). Generally, the influence of the medium is accounted for through the refractive index and the drag coefficient ad given by the Fresnel-Fizeau formula. In most laser gyros, the active medium of the ring has negligible material dispersion. In contrast, dispersion effects are expected to be substantial in compact monolithically integrated gyros based on semiconductor media.The essence of the problem of the drag coefficient is its questionable modification for rotational motion. The drag coefficient in the Fresnel-Lorentz treatment contains a dispersion-related contribution lnn/lnl. In gas or solid-state media, it gives a very small correction to the observable optical dragging. In semiconductors, the dispersion term lnn/lnl is large enough to influence not only the magnitude, but even the sign of the net drag effect. However, when this term is included in modeling of the ring laser, the gyroscopic response becomes sensitive to translational motion, in contradiction with Einstein's relativity principle. The problem was first noted in 1967 by E. Post, who somewhat arbitrarily excluded the dispersion term from the drag coefficient in order to comply with the relativity principle. Until now, no experimental verification of Post's approach was attempted.Recently, the PI has succeeded in development of monolithically integrated semiconductor ring lasers (SRLs) with relatively large (~1 cm) cavity and were able to observe the mode beating spectra from independent lasers. This opens up a possibility to perform experimental investigation of the question about contribution of dispersion term into the Sagnac effect. Experiments will be performed for precise determination of the gyroscopic coefficient in SRLs and the results will be compared with various theoretical predictions. Without these tests, the fundamental gyroscopic ratio (the ratio of Sagnac-related frequency splitting to the angular rotation rate) cannot be reliably calculated.Intellectual Merit Criterion. In spite of their promising compactness and low power consumption, SRLs have not yet been used for gyro applications, primarily due to flaws in previous designs. This project will provide scientific base for ultimate elaboration of rotation sensing problem using SRLs: how to avoid the frequency lock-in, enhance the gyro-factor, exclude excess noise, and apply novel approaches such as slow/fast light concept.The University of New Mexico (UNM) group led by Prof. Osinski has the best experience and numerous results in physics and technology of semiconductor ring lasers. The proposed work holds promise of overcoming the current limitations for integrated optoelectronic devices. The results will be important for fundamental physics of rotational motion (non-inertial frames and systems) and also for applied physics of rotation sensors and navigation gyroscopes. The results from this project are expected to lead to a new generation of rotation sensors based on slow/fast light.Broader Impacts Criterion. First demonstration of Sagnac effect in monolithically integrated SRLs coupled with conclusive studies of dispersion contribution to the magnitude of the effect will open up new opportunities for high performance, small size, low cost rotation sensors with a wide range of novel applications, ranging from robotics and toy industry to high-accuracy navigation-grade gyros.UNM has a dual commitment to excellence in research and to education opportunities for minorities and diverse society. UNM is Carnegie Doctoral/Research - Extensive and Hispanic Serving Minority Institution (37.5% of main campus enrollment are minority students). Emphasis will be placed on education and human resource development via involvement of graduate and undergraduate students in the project, and incorporation of the new knowledge gained during this project into graduate-level courses directly related to the subject of this proposal. Efforts will be made to engage members of minority groups as well as women in this project. The proposed project will create an attractive environment for students supported by other major programs already in existence at UNM that target minority students and are devoted to training of a new generation of research scientists and engineers.

0524509 Osinski叙述总结。标准理论方法在环形激光器中的应用并没有给出一个明确的定量答案，即在具有大量色散的介质（如半导体材料）中Sagnac效应的大小。通常，介质的影响是通过折射率和阻力系数α d由Fresnel-Fizeau公式给出的。在大多数激光陀螺中，环的有源介质具有可忽略的材料色散。相比之下，在基于半导体介质的紧凑型单片集成陀螺中，色散效应预计是显著的。阻力系数问题的本质是其对旋转运动的可疑修改。在菲涅耳-洛伦兹处理的阻力系数包含一个色散相关的贡献lnn/lnl。在气体或固态介质中，它对可观察到的光学拖曳给出了非常小的修正。在半导体中，色散项lnn/lnl足够大，不仅影响净阻力效应的大小，甚至影响其符号。然而，当这个术语被包括在环形激光器的建模中时，陀螺仪响应变得对平移运动敏感，这与爱因斯坦的相对性原理相矛盾。1967年，E.波斯特为了符合相对性原理，有些武断地将弥散项从阻力系数中排除。到目前为止，还没有实验验证Post的方法。最近，PI已经成功地开发了具有相对较大（~1 cm）腔的单片集成半导体环形激光器（SRL），并且能够观察到来自独立激光器的模式拍频光谱。这开辟了一个可能性，进行实验研究的问题，色散项到萨格纳克效应的贡献。将进行实验以精确确定SRL中的陀螺系数，并将结果与各种理论预测进行比较。没有这些测试，基本陀螺比（与萨尼亚克有关的频率分裂与角旋转速率的比值）就不能可靠地计算出来。尽管SRL具有紧凑性和低功耗的优点，但由于以前设计中的缺陷，SRL尚未用于陀螺仪应用。该项目将为最终阐述利用SRL的旋转传感问题提供科学基础：如何避免频率锁定，提高陀螺因子，排除多余噪声，以及应用新的方法，如慢/快光概念。由Osinski教授领导的新墨西哥州大学（UNM）小组在半导体环形激光器的物理和技术方面拥有最好的经验和众多成果。所提出的工作有希望克服目前的限制集成光电器件。这些结果对于旋转运动的基础物理学（非惯性系和系统）以及旋转传感器和导航陀螺仪的应用物理学都具有重要意义。该项目的结果有望导致新一代基于慢/快光的旋转传感器。更广泛的影响标准。Sagnac效应在单片集成SRL中的首次演示，加上色散对效应大小的贡献的结论性研究，将为具有广泛新颖应用的高性能、小尺寸、低成本旋转传感器开辟新的机会，从机器人和玩具工业到高精度导航，UNM有一个双重承诺，卓越的研究和教育机会，少数民族和多元化的社会。UNM是卡内基博士/研究-广泛和西班牙裔服务少数民族机构（37.5%的主校区招生是少数民族学生）。重点将放在教育和人力资源开发上，通过研究生和本科生参与该项目，并将该项目期间获得的新知识纳入与本提案主题直接相关的研究生课程。将努力让少数群体成员和妇女参与这一项目。拟议的项目将为学生创造一个有吸引力的环境，这些学生得到了北卡罗来纳大学现有的其他主要项目的支持，这些项目针对少数民族学生，并致力于培养新一代的研究科学家和工程师。