Energy harvesting at the nanoscale: From principles to functions

我们计划的目标是建立模型，发展理论方法和计算实现，提出新的功能，并优化在纳米尺度上运行的能量转换系统的性能。感兴趣的换能器是光伏电池、热电结和热机，如热泵和冰箱，由物理化学成分，如单分子、量子点、薄膜、有机异质结制成。使用简单的模型，我们的计划是关注这些系统中电荷和能量载流子的动力学，并询问量子效应在传输速率、损失过程、波动、电流、功率输出和效率方面的作用。感兴趣的系统的一个中心方面是，参与粒子的动力学，从而产生的操作，受到电子和非电子自由度之间相互作用的强烈影响，后者包括分子的核运动，辐射场和其他集体激励。我们工作的另一个重要方面是，它本质上偏离了传统热力学的设置，因为量子效应和操作系统与其热环境之间的强相互作用可能控制动力学。

The objectives of our program is to build models, develop theoretical methodologies and computational implementations, suggest new functions, and optimize performance of energy conversion systems operating at the nanoscale. Transducers of interest are photovoltaic cells, thermoelectric junctions, and heat engines such as heat pumps and refrigerators, made from physical-chemical components such as single molecules, quantum dots, thin films, organic hetero-junctions. Using simple models, our plan is to focus on the dynamics of charge and energy carriers in these systems, and interrogate the role of quantum effects on transfer rates, loss processes, fluctuations, currents, and power output and efficiency. A central aspect of systems of interest is that the dynamics of participating particles, thus the resulting operation, is strongly affected by the interaction between electronic and nonelectronic degrees of freedom, the latter comprising nuclear motion of molecules, radiation fields, and other collective excitations. Another nontrivial aspect of our work is that it inherently departs from the setting of traditional thermodynamics since quantum effects and strong interactions between the operating system and its thermal environment may govern the dynamics. Our program will constitute three interrelated parts: (i) Method development: We will advance various original theoretical and computational methodologies, numerically exact path integral methods, approximate approaches, and phenomenological treatments, to describe quantum dynamics of interacting systems in complex environments. We will specifically adapt these techniques to study charge, energy and spin transfer processes in representative models for molecular-based machines. (ii) Quantum thermodynamics: We will probe the emergence of macroscopic thermodynamics from quantum principles by studying minimal designs of quantum heat engines. (iii) Energy harvesting systems: Using the developed models, definitions, and theoretical and computational tools, we will simulate energy conversion processes in particular-factual nano-systems. Specifically, we will study thermoelectric and photovoltaic systems, and probe concepts of promise for an improved operation. Our work will contribute fundamental and practical insights over charge and energy transfer processes in molecular systems, components of electronic and thermal devices. As well, developed methods could be applied to describe processes at the core of chemical reactivity in solution and decoherence effects in quantum information technologies. The proposed research program will contribute to the advancement of knowledge, with the development of first-principle approaches for treating quantum many-body effects in complex systems, and to emerging technologies, by suggesting novel designs for nanoscale energy conversion systems.