RUI: Helium Adsorption on Alkali Surfaces and Graphite: Computer Simulation Studies

RUI：氦在碱表面和石墨上的吸附：计算机模拟研究

• 批准号: 9802803
• 负责人: Massimo Boninsegni
• 金额: $ 9万
• 依托单位: San Diego State University Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9802803&HistoricalAwards=false
• 关键词: RUI; Helium; Adsorption; Alkali; Surfaces

9802803 Boninsegni This is a Research at Undergraduate Institutions (RUI) Award for a theoretical program consisting of numerical studies of Helium physisorption. Computer simulations of Helium adsorbed on alkali surfaces and on graphite will be performed using the Path Integral Monte Carlo (PIMC) method. Available, realistic interatomic potentials will be adopted to model the interaction among Helium atoms, as well as between Helium atoms and the substrate. Specific objectives of the proposed research effort will be the study of the physical properties of a 4He adsorbate on the surface of alkali metals, as well as on a graphite substrate. The unifying theme of this research is the topic of physisorption, of great interest in condensed matter physics, and one where relatively little numerical simulation has been performed so far. This research is also expected to offer novel insight into such fundamental theoretical issues as phase transitions in reduced dimensions and monolayer superfluidity. The PIMC method is arguably the most powerful numerical tool currently available to calculate thermodynamic properties of quantum many-body systems directly from a microscopic Hamiltonian. The use of this technique in this research can afford quantitative predictions for a variety of adsorption phenomena involving differently attractive substrates and a quantum adsorbate; thus, it will help in the interpretation of several ongoing experiments involving Helium adsorption. %%% This is a Research at Undergraduate Institutions (RUI) Award to support a program of numerical simulation of the adsorption of Helium on various substrates including graphite. The numerical simulations will support a number of experiments being done elsewhere. The simulations will also provide insight into phase transitions of adsorbates on surfaces and on monolayer superfluidity. ***

9802803 Boninsegni这是一个本科生研究机构(RUI)奖，表彰一个由氦物理吸收的数值研究组成的理论项目。用路径积分蒙特卡罗(PIMC)方法对氦在碱表面和石墨表面的吸附进行了计算机模拟。将采用现有的、现实的原子间相互作用势来模拟氦原子之间以及氦原子与衬底之间的相互作用。拟议研究工作的具体目标将是研究4He吸附在碱金属表面以及石墨衬底上的物理性质。这项研究的统一主题是物理吸附，这是凝聚态物理中非常感兴趣的主题，到目前为止，进行的数值模拟相对较少。这项研究还有望为降维相变和单层超流等基本理论问题提供新的见解。PIMC方法可以说是目前可用的最强大的数值工具，可以直接从微观哈密顿量计算量子多体系统的热力学性质。在这项研究中使用这项技术可以提供对各种吸附现象的定量预测，这些现象涉及不同的吸引人的底物和量子吸附物；因此，它将有助于解释正在进行的几个涉及氦吸附的实验。%这是一个本科生研究机构(RUI)奖，以支持氦在包括石墨在内的各种衬底上吸附的数值模拟计划。数值模拟将支持在其他地方进行的一些实验。这些模拟还将提供对表面上的吸附物的相变和单层超流动性的洞察。***