Lasing Without Inversion in He and He-like Ions in XUV and X-Ray Regions

He 和类 He 离子在 XUV 和 X 射线区域中无反转的激光发射

• 批准号: 1068554
• 负责人: Szymon Suckewer
• 金额: $ 52.48万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1068554&HistoricalAwards=false
• 关键词: Lasing; Without; Inversion; He; like

This project is to demonstrate Lasing Without Inversion (LWI) in extreme vacuum ultraviolet (XUV) and X-ray regions. The basis for the project is the recently developed theory of LWI in He atoms at 58 nm and in He-like ions of triply ionized B at 6.1 nm, as transient lasing in a three-level system. The important features of LWI are the coherent control in the XUV and X-ray, and that lasing wavelengths rapidly decrease with increasing Z. Such lasing has common features with Dicke super-radiance, and, hence, can yield strong XUV and X-ray lasing. The quantum coherence phenomenon in atomic and radiation physics has led to many interesting and unexpected consequences. For example, an atomic ensemble prepared in a coherent superposition of states will yield self-induced transparency, photon echo, and coherent Raman beats. By preparing an atomic system in a coherent superposition of states, under certain conditions it is possible for atomic coherence to cancel absorption but not emission, which is the basis for LWI. Frequently, this is accomplished in three- or four-level atomic systems in which there are coherent routes for absorption that can destructively interfere, thus leading to the cancellation of absorption. A small population in the excited state of the system can lead to net gain. Previous LWI studies have been limited primarily to the visible and infrared regions of the spectrum. This is the fist attempt to produce lasing in the XUV and X-ray regions, which are difficult to generate, via LWI. Achieving the proposed LWI for XUV and farther extending it to the X-ray region would provide an excellent "tool" for researchers who need portable, inexpensive coherent XUV and X-ray devices.Ths research will provide an excellent opportunity for teaching and training of graduate students, and also for very advanced undergraduate students. Several of our former graduate students are already accomplished scientists and administrative leaders in the areas of basic laser and plasma theory, experiments, applications of lasers and plasma physics, as well as in computer simulations of experiments and laser applications.

本项目旨在演示极真空紫外（XUV）和X射线区域的无反转激光（LWI）。该项目的基础是最近发展的理论LWI在He原子在58 nm和类He离子的三重电离B在6.1 nm，作为瞬态激光在一个三能级系统。LWI的重要特征是在XUV和X射线中的相干控制，以及激光波长随Z的增加而迅速减小。这种激光与迪凯超辐射具有共同的特征，因此可以产生强的XUV和X射线激光。 原子和辐射物理中的量子相干现象导致了许多有趣和意想不到的结果。 例如，在相干叠加态中制备的原子系综将产生自诱导透明、光子回波和相干拉曼拍频。通过在相干叠加态中制备原子系统，在一定条件下，原子相干性可以消除吸收而不是发射，这是LWI的基础。通常，这是在三能级或四能级原子系统中实现的，在这些系统中存在相干的吸收路径，这些吸收路径可以相消干涉，从而导致吸收的抵消。 在系统的激发态中的少量粒子数可以导致净增益。 以前的LWI研究主要限于光谱的可见光和红外区域。 这是第一次尝试在XUV和X射线区域产生激光，这是很难产生，通过LWI。实现所提出的XUV激光干涉仪并将其进一步扩展到X射线领域，将为需要便携式、廉价的相干XUV和X射线设备的研究人员提供一个极好的“工具”，这一研究将为研究生的教学和培训提供一个极好的机会，也为非常高的本科生提供了一个很好的机会。 我们以前的几个研究生已经完成了科学家和行政领导人在基本的激光和等离子体理论，实验，激光和等离子体物理的应用领域，以及在实验和激光应用的计算机模拟。