Finkelstein-Shapiro Daniel, Urdaneta Ines, Calatayud Monica, Atabek Osman, Mujica Vladimiro, Keller Arne
Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85282, USA.
Sorbonne Universités, UPMC Université Paris 06, UMR 7616, Laboratoire de Chimie Théorique, F-75005 Paris, France.
Phys Rev Lett. 2015 Sep 11;115(11):113006. doi: 10.1103/PhysRevLett.115.113006. Epub 2015 Sep 10.
The scattering amplitude from a set of discrete states coupled to a continuum became known as the Fano profile, characteristic for its asymmetric line shape and originally investigated in the context of photoionization. The generality of the model and the proliferation of engineered nanostructures with confined states gives immense success to the Fano line shape, which is invoked whenever an asymmetric line shape is encountered. However, many of these systems do not conform to the initial model worked out by Fano in that (i) they are subject to dissipative processes and (ii) the observables are not entirely analogous to the ones measured in the original photoionization experiments. In this Letter, we work out the full optical response of a Fano model with dissipation. We find that the exact result for the excited population, Raman, Rayleigh, and fluorescence emission is a modified Fano profile where the typical line shape has an additional Lorentzian contribution. Expressions to extract model parameters from a set of relevant observables are given.
一组与连续态耦合的离散态的散射振幅被称为法诺分布，其特征在于不对称的线形，最初是在光电离的背景下进行研究的。该模型的通用性以及具有受限态的工程纳米结构的大量涌现，使得法诺线形取得了巨大成功，每当遇到不对称线形时都会提及它。然而，这些系统中的许多并不符合法诺最初提出的模型，原因在于：（i）它们会受到耗散过程的影响；（ii）可观测的量并不完全类似于在原始光电离实验中测量的量。在本信函中，我们计算了具有耗散的法诺模型的完整光学响应。我们发现，激发态粒子数、拉曼散射、瑞利散射和荧光发射的精确结果是一种修正的法诺分布，其中典型的线形有一个额外的洛伦兹贡献。文中给出了从一组相关可观测值中提取模型参数的表达式。
