Spectroscopy is an indispensable tool for understanding the structures and dynamics of molecular systems. However, computational modeling of spectroscopy is challenging due to the exponential scaling of computational complexity with system sizes unless drastic approximations are made. Quantum computers could potentially overcome these classically intractable computational tasks, but the existing approaches using quantum computers to simulate spectroscopy can only handle isolated and static molecules. In this work, we develop a workflow that combines multi-scale modeling and a time-dependent variational quantum algorithm to compute the linear spectroscopy of systems interacting with their condensed-phase environment via the relevant time correlation function. We demonstrate the feasibility of our approach by numerically simulating the UV–vis absorption spectra of organic semiconductors. We show that our dynamical approach captures several spectral features that are otherwise overlooked by static methods. Our method can be directly used for other linear condensed-phase spectroscopy and could potentially be extended to nonlinear multi-dimensional spectroscopy.

中文翻译：

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使用近程数字量子计算机模拟凝聚相光谱

光谱学是理解分子系统结构和动力学不可或缺的工具。然而，除非进行剧烈的近似，否则由于计算复杂性随系统大小呈指数缩放，光谱学的计算建模具有挑战性。量子计算机有可能克服这些传统上难以处理的计算任务，但现有的使用量子计算机模拟光谱的方法只能处理孤立和静态的分子。在这项工作中，我们开发了一个工作流程，结合多尺度建模和时间相关变分量子算法，通过相关的时间相关函数计算与其凝聚相环境相互作用的系统的线性光谱。我们通过数值模拟有机半导体的紫外-可见吸收光谱来证明我们方法的可行性。我们展示了我们的动态方法捕获了静态方法忽略的几个光谱特征。我们的方法可以直接用于其他线性凝聚相光谱，并有可能扩展到非线性多维光谱。