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Modular path integral for finite-temperature dynamics of extended systems with intramolecular vibrations
1Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA.
We present a numerically exact algorithm for calculating dynamical properties of extended systems. This method now includes harmonic bath modes and finite temperatures for accurate reduced density matrix calculations.
Area of Science:
- Quantum dynamics
- Condensed matter physics
- Computational chemistry
Background:
- The modular path integral decomposition is a linear-scaling algorithm for calculating dynamical properties.
- Previous work extended this method to wavefunction propagation with non-diagonal couplings.
Purpose of the Study:
- To extend the modular path integral decomposition to calculate reduced density matrices.
- To incorporate arbitrary numbers of coupled harmonic bath modes at finite temperatures.
Main Methods:
- The method incorporates harmonic bath modes via derived analytical influence functional factors.
- It calculates reduced density matrices for extended systems with local couplings.
Main Results:
- The algorithm accurately calculates dynamical properties including effects of harmonic modes and finite temperature.
- Representative applications demonstrate its utility for spin arrays and J-aggregates.
Conclusions:
- The extended method provides a powerful tool for studying quantum dynamics in complex systems.
- It enables accurate simulations of systems with intramolecular vibrations and dissipative interactions.
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