SBIR Phase I: Ultraviolet laser for ultra-high-resolution photoemission spectroscopy

SBIR 第一阶段：用于超高分辨率光电子能谱的紫外激光器

• 批准号: 0711924
• 负责人: Andrew Merriam
• 金额: $ 10万
• 依托单位: ACTINIX
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2007-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0711924&HistoricalAwards=false
• 关键词: SBIR; Phase; Ultraviolet; laser; ultra

This Small Business Innovation Research Phase I project addresses an immediate need for a short-wavelength, narrow-bandwidth, high-brightness light source for ultra-high-resolution angle-resolved photoemission spectroscopy (ARPES). Low-photon-energy laser sources (~6 eV) have recently been applied to ARPES-based studies of superconducting material properties. Although these lasers have demonstrated the advantages of narrow bandwidths, much higher photon energies than those previously obtained will be required for wide acceptance within the industry. Howeve, solid-state nonlinear media cannot be used to generate light with sufficiently high photon energy due to strong absorption. The specific innovation of the proposed research is a high-efficiency gas-phase nonlinear frequency converter that may be harnessed to generate high average powers at photon energies near 11 eV. The high overall efficiency of this coherent source is due to a fortuitous coincidence between an atomic level and a high-power diode pumped infra-red laser. The nonlinear converter maintains the narrow-bandwidth of the drive laser to achieve sub-meV energy resolution at high photon energies. In the Phase I effort, the conversion efficiency of a phase-matched gas-phase nonlinear mixer will be measured in order to verify the technical and commercial feasibility of the light source.The commercial application of this project is primarily to advance the study of modern superconducting materials. As is well-known, room-temperature superconductors with high current-carrying capability will transform every aspect of the energy sector. However, much theoretical and experimental work remains before this elusive goal may be realized. Photoemission spectroscopy is a vital tool for understanding the mechanisms of high temperature superconductivity, but at present, many competing theoretical models of superconductivity cannot be resolved at the current ~5-meV energy resolution limit set by traditional synchrotron light sources. In conjunction with improvements in electron analyzer hardware, the proposed light source will dramatically increase the energy resolution of photoemission spectroscopy to the sub-meV level. The capabilities of the proposed light source will complement those of the workhorse synchrotron, and enable the next generation of superconducting research.

这个小型企业创新研究第一阶段项目解决了超高分辨率角分辨光电子能谱（ARPES）对短波长、窄带宽、高亮度光源的迫切需求。低光子能量激光源（~6 eV）最近已被应用于基于ARPES的超导材料性质的研究。虽然这些激光器已经证明了窄带宽的优点，但要在工业中广泛接受，需要比以前获得的光子能量高得多的光子能量。然而，由于强吸收，固态非线性介质不能用于产生具有足够高光子能量的光。拟议的研究的具体创新是一种高效的气相非线性频率转换器，可以利用它在接近11 eV的光子能量下产生高平均功率。这种相干光源的高整体效率是由于原子水平和高功率二极管泵浦的红外激光器之间的偶然巧合。非线性转换器保持驱动激光器的窄带宽，以在高光子能量下实现亚meV能量分辨率。在第一阶段的工作中，将测量相位匹配气相非线性混频器的转换效率，以验证光源的技术和商业可行性。该项目的商业应用主要是推进现代超导材料的研究。众所周知，具有高载流能力的室温超导体将改变能源部门的各个方面。然而，在实现这一难以捉摸的目标之前，还有许多理论和实验工作要做。光电子能谱是理解高温超导机制的重要工具，但目前，许多相互竞争的超导理论模型无法在传统同步辐射光源设定的当前~5-meV能量分辨率极限下解析。结合电子分析仪硬件的改进，所提出的光源将大大提高光电子能谱的能量分辨率到亚毫电子伏的水平。拟议中的光源的能力将补充主力同步加速器的能力，并使下一代超导研究成为可能。