Theory of Time-Dependent Phenomena in Quantum Many-Body Systems

9706788 Vignale这项资助将支持一位处于职业生涯中期的PI在时间相关密度泛函理论的一些基本方面的工作。PI开创了广义电流密度泛函理论来描述弱扰动电位下的高频效应。广义理论有望统一处理从标准线性响应和输运到非线性和非摄动现象和参数不稳定性等大类现象。PI将研究精确解作为基准，以了解精确交换相关势的严格结构。该理论也将推广到包括电子自旋自由度。理论工作将受益于金属中集体激发的色散和寿命实验以及数字设计量子阱中的激发。此外，PI还计划研究量子霍尔系统边缘的激发。这位职业生涯中期的PI是研究金属中电子随时间变化性质的理论形式主义发展的先驱。这项工作被广泛地称为电流密度泛函理论。在目前的资助下，他计划开发一种统一的方法来处理原子、分子和金属对强、高频电磁场的反应。具体的影响包括非线性现象的研究，以及金属和数字设计量子阱中的参数不稳定性。他还计划研究高场下电子的特殊性质，即量子霍尔效应中与边缘态相关的特征。* * *

9706788 Vignale This grant will support the work of a mid-career PI on some fundamental aspects of time dependent density functional theory. The PI has pioneered the generalized current- density functional theory to describe the high frequency effects under weak perturbing potentials. The generalized theory has the prospect of a unified treatment of a large class of phenomena ranging from standard linear response and transport to nonlinear and nonperturbative phenomena and parametric instabilities. The PI will study exact solutions as benchmarks, to learn about the rigorous structure of the exact exchange correlation potentials. The theory will also be generalized to include the electronic spin degree of freedom. The theoretical work will benefit from experiments on the dispersion and lifetime of collective excitations in metals and also on excitations in digitally designed quantum wells. In addition the PI is also planning to investigate the excitations at the edges of quantum Hall systems. %%% This mid-career PI was a pioneer in the development of a theoretical formalism to study the time dependent properties of electrons in metals. This work is widely known as the current-density functional theory. In the present grant, he is planning to develop a unified treatment of the response of atoms, molecules and metals to intense and high frequency electromagnetic fields. The specific effects include a study of nonlinear phenomena and also parametric instabilities in metals and in digitally designed quantum wells. He is also planning to study the special properties of electrons at high fields, the features associated with the edge states in a quantum Hall effect. ***