MRI: Development of a Combination High Resolution and Low Current Density Inverse Photoemission Spectrograph for Research and Eduction

MRI：开发用于研究和教育的高分辨率和低电流密度逆光电发射光谱仪组合

• 批准号: 0421177
• 负责人: Robert Opila
• 金额: $ 18.98万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0421177&HistoricalAwards=false
• 关键词: MRI; Development; Combination; Resolution; Low

Recently, tremendous advances have been achieved in the development of new materials such as highly correlated electron systems, nanoscale materials, organic semiconductors and promising species for molecular electronics. While photoelectron spectroscopy has played a central role in establishing key properties of these materials, there has been markedly less progress towards understanding the spectral function above EF. Inverse photoemission (IPE) spectroscopy is the natural choice for probing this energy range, but high current densities and low energy resolution limit its application to these interesting systems. The proposed instrument will greatly relieve these shortcomings and open to experimental scrutiny the spectral function above the Fermi level of these interesting materials. The information gained from this new instrument will enable intelligent design of candidate species for molecular electronics or organic semiconductor applications. Similarly it will test our current theoretical understanding of highly correlated electron systems by experimentally probing the energy and momentum dependence of the spectral function in a new regime. We will develop and construct the prototype for a new generation of inverse photoemission spectrographs that will serve the dual demands of modern materials science -- low current density and high energy resolution -- while maintaining high count rates. This objective will be achieved by a design principle that exploits the compatibility between a fast (f/5) normal incidence grating spectrograph and the spatially extended linear electron spot produced by either of two sources: a modified, high perveance electron gun, and a high resolution electron energy monochromator. This dual source approach will enable us to perform rapid exploratory measurements and then investigate interesting features either with low current densities (~0.1 mA/mm2) or with high resolution (~ 50 meV) at good count rates (~ 100 Hz). The instruments will serve the research community at the University of Delaware, Rutgers University, and other neighboring institutions. With the proposed instrument, the PI's will add to their strong track record of outreach both within and out of the academic communities, as well as ensure members of underrepresented groups have direct participation in our research activities.The proposed instrument will give previously unattainable experimental access a wide range of problems in modern condensed matter and materials physics, semiconducting organic materials, organic molecular electronics, modern electronics, and superconductivity. This new instrument will probe, with very high energy resolution, the unfilled electronic levels in conducting systems with minimal perturbation of the other charge carriers and minimal damage to the materials system. We propose a program to develop and construct the prototype for a new generation of inverse photoemission spectrographs that will serve the dual demands of modern materials science -- low current density and high energy resolution -- while maintaining high count rates. While traditional photoelectron spectroscopy has played a central role in establishing key properties of the bonding and charge carriers in the filled electronic levels of these materials, there has been markedly less progress towards understanding the unfilled levels. Inverse photoemission (IPE) spectroscopy is the natural choice for probing this energy range, but high current densities and low energy resolution limit its application to these interesting systems. The proposed instrument will greatly relieve these shortcomings. The information gained from this new instrument will enable intelligent design of candidate species for molecular electronics or organic semiconductor applications. Similarly it will test our current theoretical understanding of highly correlated electron systems, for example, superconductors, by experimentally probing the energy and momentum dependence of the spectral function in a new regime. The instruments will serve the research community at the University of Delaware, Rutgers University, and other neighboring institutions. With the proposed instrument, the PI's will add to their strong track record of outreach both within and out of the academic communities, as well as ensure members of underrepresented groups have direct participation in our research activities.

最近，在新材料的开发中取得了巨大的进步，例如高度相关的电子系统，纳米级材料，有机半导体和有前途的分子电子物种。 尽管光电子光谱在建立这些材料的关键特性方面起着核心作用，但在理解EF上方的光谱函数方面的进展显着较少。 逆光发射（IPE）光谱是探测此能量范围的自然选择，但是高电流密度和低能分辨率将其应用于这些有趣的系统。 所提出的仪器将极大地缓解这些缺点，并对这些有趣材料的费米水平以上的光谱函数进行实验审查。 从这种新仪器中获得的信息将使候选物种智能设计用于分子电子或有机半导体应用。 同样，它将通过实验探测新制度中光谱函数的能量和动量依赖性来测试我们对高度相关电子系统的当前理论理解。 我们将开发和构建新一代的逆光发射光谱仪的原型，这些谱图将满足现代材料科学的双重需求 - 低电流密度和高能量分辨率 - 同时保持高计数速率。 该目标将通过设计原理来实现，该设计原理利用了快速（f/5）正常入射光谱仪与由两个来源中的任何一个产生的空间扩展的线性电子点之间的兼容性：一种改良的，高的PerVeance电子枪，高分辨率电子枪和高分辨率电子能量单色器。 这种双源方法将使我们能够进行快速的探索性测量，然后以低电流密度（〜0.1 mA/mm2）或高分辨率（〜50 meV）的良好计数速率（〜100 Hz）研究有趣的特征。 这些工具将为特拉华大学，罗格斯大学和其他邻近机构的研究社区提供服务。 借助拟议的仪器，PI将增加他们在学术社区内外的强烈宣传记录，并确保代表性不足的群体的成员直接参与我们的研究活动。拟议的仪器将使以前无法实现的实验访问现代凝聚力物质和材料物理学，半构造物质，有机材料，有机化学，有机化的电子，有机学，有机化学，有机材料。 该新仪器将以非常高的能量分辨率进行探测，在导电系统中，未填充的电子水平的摄动最小，对其他电荷载体的扰动最小，对材料系统的损害最小。 我们提出了一个计划，以开发和构建新一代的逆光发射光谱仪的原型，该光发射光谱仪将满足现代材料科学的双重需求 - 低电流密度和高能量分辨率 - 同时保持高计数速率。 尽管传统的光电子光谱在这些材料的填充电子水平中建立粘结和电荷载体的关键特性方面发挥了核心作用，但在理解未填充水平方面的进展显着较少。 逆光发射（IPE）光谱是探测此能量范围的自然选择，但是高电流密度和低能分辨率将其应用于这些有趣的系统。 拟议的工具将极大地缓解这些缺点。 从这种新仪器中获得的信息将使候选物种智能设计用于分子电子或有机半导体应用。 同样，它将通过实验探测光谱函数在新制度中的能量和动量依赖性来测试我们对高度相关电子系统（例如超导体）的当前理论理解。 这些工具将为特拉华大学，罗格斯大学和其他邻近机构的研究社区提供服务。 借助拟议的工具，PI将增加他们在学术社区内外的强大宣传记录，并确保代表性不足的群体的成员直接参与我们的研究活动。