Molecular Nanoelectronics: Simulation from Molecules to Circuits

拟议研究的目标是建立一个由来自分子电子学化学、分子尺度的电子传导物理、先进的电子结构、传输特性和实验协议以及硅器件和电路技术的专家组成的协作团队，以应对量子尺度上的电子学挑战。这将需要涉及多个长度和能量尺度的建模和仿真，从原子哈密顿量到复杂电路。利用分子自组装、界面控制和扫描探针的使用方面的进展，我们将检查主体接触之间的分子桥，并将实验中观察到的一般特征与模拟相关联，该模拟根据耦合到主体金属铅的分子的格林函数来计算朗道电导。我们将从理论上分析已观察到的非常新的、有趣的、可能有用的可逆开关特性。这些系统通常由硬接触(半导体或金属)和软分子组成，这些分子可能会表现出动态的结构修改。这一多学科、小组工作的目标是：i)了解硬接触之间的分子桥的物理和电子结构以及振动相互作用，ii)从理论上理解目前正在观察的分子的有趣的非线性I-V特性，并将它们与分子结构联系起来，iii)设计基于物理的提取方法，从分子电子器件的哈密顿量建立电路模型，并利用这些知识和开发的模拟工具从器件和电路的角度识别有希望的分子结构。发展对如何将电子设备和电路功能与分子结构联系起来的理解是拟议研究的主要目标。这项工作的其他重要组件和产品包括：i)为分子纳米电子学开发了一组强调分子器件的结构/功能关系并将它们连接到电路和系统的宏观世界的社区代码，ii)允许研究人员建议特定结构、电极和界面连接、预测器件的电性能并提取电路模型的方法，iii)独特的软件基础设施，即计算电子中心，它将允许用户通过WWW浏览器访问和操作模拟工具，iv)一组课程，将通过这种多学科的努力得到丰富和扩展，V)与学术界(耶鲁大学的Reed)和工业界领先的实验工作密切互动；vi)与NIST小组建立伙伴关系，提供先进分子电子结构方法方面的专业知识；vii)与国际中心，特别是委内瑞拉中央大学合作；viii)材料世界模块计划中的高中教学模块；ix)与半导体研究公司和个别半导体公司密切互动，将自组装分子电子学的想法和方法引入电子行业。

The objective of the proposed research is to establish a collaborative team of experts from the chemistry of molecular electronics, the physics of electronic conduction at the molecular scale, advanced electronic structure, transport properties and experimental agreement, and silicon device and circuits technology to address the challenges of electronics at the quantum scale. This will require modeling and simulation involving multiple length and energy scales, starting from atomic Hamiltonians and going to complex circuits. Leveraging advances in molecular self-assembly, interfacial control, and the use of scanning probes, we will examine molecular bridges between bulk contacts, and relate the general features observed in experiments to simulations which compute the Landauer conductance from the Green's function of the molecule coupled to bulk, metal leads. Very recent, interesting, and potentially useful, reversible switching characteristics that have been observed will be analyzed theoretically. The systems typically consist of hard contacts (semiconductors or metals) and soft molecules that may exhibit dynamic structure modification. The objectives of this multi-disciplinary, small group effort are: i) to understand the physical and electronic structure and vibronic interactions of molecular bridges between hard contacts, ii) to develop a theoretical understanding of the interesting nonlinear I-V characteristics of molecules that are now being observed and to relate them to the structure of the molecule, iii) to devise methods for extracting physics-based, circuit models from the Hamiltonian of molecular electronic devices and iv) to use this knowledge and the simulation tools developed to identify molecular structures that are promising from a device and circuits perspective.The development of an understanding of how to relate electronic device and circuit function to molecular structure is the key objective of the proposed research. Other important components and products of this work include: i) the development of a set of 'community codes' for molecular nanoelectronics that emphasize the structure/function relationship of molecular devices and that connect them to the macroscopic world of circuits and systems, ii) a methodology to allow a researcher to suggest a particular structure, electrodes, and interfacial linkages, predict the electrical performance of the device, and to extract a circuit model, iii) a unique software infrastructure, The Computational Electronics Hub, that will permit users to access and operate simulation tools through a WWW browser, iv) a set of courses that will be enriched and expanded by this multidisciplinary effort, v) close interactions with leading experimental efforts in academia (Reed at Yale) and industry, vi) a partnership with the NIST group to provide expertise in advanced molecular electronic structure methods, vii) collaboration with international centers, particularly the Central University of Venezuela, viii) A high-school level teaching module in the Materials World Modules program, and ix) close interactions with the Semiconductor Research Corporation and with individual semiconductor companies to bring ideas and approaches of self-assembled molecular electronics to the electronics industry.