Spectral Densities, Structured Noise and Ensemble Averaging within Open Quantum Dynamics

Abstract

Although recent advances in simulating open quantum systems have lead to significant progress, the applicability of numerically exact methods is still restricted to rather small systems. Hence, more approximate methods remain relevant due to their computational efficiency, enabling simulations of larger systems over extended timescales. In this study, we present advances for one such method, namely the Numerical Integration of Schrödinger Equation (NISE). Firstly, we introduce a modified ensemble-averaging procedure that improves the long-time behavior of the thermalized variant of the NISE scheme, termed Thermalized NISE. Secondly, we demonstrate how to use the NISE in conjunction with (highly) structured spectral densities by utilizing a noise generating algorithm for arbitrary structured noise. This algorithm also serves as a tool for establishing best practices in determining spectral densities from excited state calculations along molecular dynamics or quantum mechanics/molecular mechanics trajectories. Finally, we assess the ability of the NISE approach to calculate absorption spectra and demonstrate the utility of the proposed modifications by determining population dynamics.

48 pages, 13 figures. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in J. Chem. Phys. 161, 134101 (2024) and may be found at https://doi.org/10.1063/5.0224807

References in corpus (24)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• PyTorch: An Imperative Style, High-Performance Deep Learning Library
• Perspective: Numerically "exact" approach to open quantum dynamics: The hierarchical equations of motion (HEOM)
• Multilayer multi-configuration time-dependent Hartree method: implementation and applications to a Henon-Heiles Hamiltonian and to pyrazine
• Excitons in a Photosynthetic Light-Harvesting System: A Combined Molecular Dynamics/Quantum Chemistry and Polaron Model Study
• Controlling open quantum systems: Tools, achievements, and limitations
• Hierarchy of stochastic pure states for open quantum system dynamics
• On the alternatives for bath correlators and spectral densities from mixed quantum-classical simulations
• Numerically exact open quantum systems simulations for arbitrary environments using automated compression of environments
• Taming Quantum Noise for Efficient Low Temperature Simulations of Open Quantum Systems
• Multi-Layer Multi-Configuration Time-Dependent Hartree (ML-MCTDH) Approach to the Correlated Exciton-Vibrational Dynamics in the FMO Complex
• A Comprehensive Review of Quantum Random Number Generators: Concepts, Classification and the Origin of Randomness
• Generalization of the hierarchical equations of motion theory for efficient calculations with arbitrary correlation functions
• Memory-assisted exciton diffusion in the chlorosome light-harvesting antenna of green sulfur bacteria
• Generalized theory of pseudomodes for exact descriptions of non-Markovian quantum processes
• Iterative algorithm versus analytic solutions of the parametrically driven dissipative quantum harmonic oscillator
• Exact open quantum system dynamics using the Hierarchy of Pure States (HOPS)
• Universal Prony fitting decomposition for optimized hierarchical quantum master equations
• Structural fluctuations and quantum transport through DNA molecular wires: a combined molecular dynamics and model Hamiltonian approach
• Time-Dependent Atomistic Simulations of the CP29 Light-Harvesting Complex
• Survey of the Hierarchical Equations of Motion in Tensor-Train format for non-Markovian quantum dynamics
• Simulating optical linear absorption for mesoscale molecular aggregates: an adaptive hierarchy of pure states approach
• Treatment of Herzberg-Teller and non-Condon effects in optical spectra with Hierarchical Equations of Motion
• Bexcitonics: Quasi-particle approach to open quantum dynamics